SSPC Protective Coatings Inspector Training and Certification (PCI) Study Guide
PCI Study Guide- October 2007 Table of Contents Module One: Protecting Steel from Corrosion: The Role of Protective Coatings……………………………………………………………………………2 Module Two: The Roles of Quality Assurance (QA) and Quality Control (QC) Inspection Personnel on a Coating Project………………………………………...7 Module Three: Surface Preparation Methods, Industry Standards, and Inspection………………………….……………………………………………….15 Module Four: Practical Arithmetic for the Coatings Inspector…………………….31 Module Five: Coating Mixing, Thinning, and Application: Equipment Overview and Inspection Techniques……………………………………………………………...43 Module Six: Industrial and Marine Protective Coatings and Coating Systems……………………………………………………………………………..62 Module Seven: Specialty Inspection Projects……………………………………...69 Module Eight: Coating Failures: Investigation Procedures and Case Studies………………………………………………………………………………74 Module Nine: Inspector Safety……………………………………………………..77 Module Ten: Navigating Coatings Specification………………………………….. 82 Module Eleven: Specification Review and Pre-Construction Conference; Inspection Plan Development for the Inspection of Fuel Tank Lining Installation…………………..84 Module Twelve: Project Inspection Workshop……………………………………...85 Appendix A Quiz Answer Keys…………………………………………………………....A-1 Appendix B Glossary………………………………………………………………………B-1 Appendix C Arithmetic…………………………………………………………………….C-1
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PCI Study Guide- October 2007 Module One: Protecting Steel from Corrosion: The Role of Protective Coatings Module one explains how coatings protect metals from corroding. Corrosion is a process where man-made metals give up energy and return to their natural state. Some manmade metals have a stronger propensity to corrode than others, but all man-made metals corrode eventually. Only four elements need to be present for corrosion to occur: an anode, a cathode, a metallic pathway, and an electrolyte. While the corrosion of manmade metals cannot be completely halted, it can be controlled. The most widely used method to prevent/slow corrosion today, particularly on carbon steel, is the application of high performance coatings. Module One explains how today’s high performance coatings use barrier protection, sacrificial or cathodic protection, and inhibitive protection to protect modern day steel structures from the inevitable process of deterioration and decay. Learning Outcomes At the completion of this module you should be able to: - Identify the elements of a corrosion cell - Describe the corrosion of man-made metals - Explain how industrial coatings control corrosion - Describe alternative methods used to protect carbon steel from corrosion Identify the Elements of a Corrosion Cell Corrosion will occur when four required elements are present. If any one of the elements is missing, the corrosion process will not proceed. The required elements, which compose a “corrosion cell” are: 1. Anode 2. Cathode 3. Metallic Pathway (connecting the anode and cathode) 4. Electrolyte Corrosion of Man-made Metals A metal in its pure form will begin to corrode and revert to its natural state when all of the elements of a corrosion cell are present. Exposure to air and water are usually enough to get the process started and the metal surface begins to corrode and oxidize (oxidation is another term that is sometimes used along with corrosion and simply refers to reaction with oxygen.) Explain How Industrial Coatings Control Corrosion Corrosion of metals really cannot be completely stopped. Slowing down the process as much as possible is the only option to preserve the metal and this is where protective coatings play a crucial role. Coatings are considered to function as a protective layer in three different ways: by providing barrier, sacrificial or inhibitive protection.
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PCI Study Guide- October 2007 Describe Alternative Methods Used to Protect Carbon Steel from Corrosion Cathodic protection can be provided by passive or active means. Passive cathodic protection can be accomplished by attaching a dissimilar metal directly to a metal substrate to act as a sacrificial anode to corrode preferentially. Active cathodic protection can be provided by applying or “impressing” an electrical current to the structure.
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PCI Study Guide- October 2007 Module One: Protecting Steel from Corrosion: The Role of Protective Coatings Quiz 1 1. Corrosion is defined as the ________________ of _________________________. 2. Carbon steel _____________________ energy during the corrosion process. 3. The use of ________________ __________________ is the most widely used method of corrosion control. 4. List four elements of a corrosion cell: _____________________________ _____________________________ _____________________________ _____________________________ 5. Which of the four elements in question 4 does a protective coating prevent from contacting the steel? __________________________________________________ 6. When corrosion occurs, the _____________________ depletes or decays. 7. If a copper pipe is combined to an aluminum pipe without an insulator, which metal represents the anode? _____________________________________________________ 8. List two dissimilar metals that are intentionally coupled in the protective coatings industry as a method of corrosion prevention? ________________________ and ____________________________ 9. What type of chemical will deteriorate uncoated weathering steel? _________________________ 10. ___________________ pigments form plate-like layers and provide barrier protection to steel surfaces. 11. What two elements are prevented from contacting steel when a barrier-type coating is employed? _____________________ and ___________________________ 12. Zinc-rich primers protect the steel by _______________ and ________________ protection. 13. Thermal spray metallizing and galvanizing protect the steel by _______________ and ________________ protection.
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PCI Study Guide- October 2007 14. Borates, chromates, phosphates and other pigments protect the steel by _________________. 15. Cathodic protection can be in the form of ______________________ _______________ or __________________ current. 16. ___________________ is considered passive cathodic protection. 17. ___________________ is considered active cathodic protection. 18. Cathodic protection is used in conjunction with ___________________ _________________. 19. _________________ and __________________ are metals that form a protective oxidation layer. 20. When corrosion occurs, the steel is __________________ energy.
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PCI Study Guide- October 2007 Module One: Protecting Steel from Corrosion: The Role of Protective Coatings Supplemental Reading -
Corrosion and Coatings: An Introduction to Corrosion for Coatings Personnel (SSPC Item #98-08) Corrosion Prevention by Protective Coatings (SSPC Item #00-16) Value of Coatings (SSPC Item VT-VOC)
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PCI Study Guide- October 2007 Module Two: The Roles of Quality Assurance (QA) and Quality Control (QC) Inspection Personnel on a Coating Project Module Two compares the roles of QA and QC inspectors on coatings projects. All too often, the lines between the QC and the QA on a coatings project get blurred. When that happens, the scope of work and responsibility for that work can get blurred in the process. This module is designed to clarify the common roles and responsibilities of both the contractor’s QC inspector and the Owner’s QA inspector. This is a textbook: the way it would work in a perfect world, but it is helpful to know how things “could/should” work before getting caught up in the day to day rush of a real world coatings project. Module Two compares and contrasts the role of the QA and QC inspector on a typical coatings project. The commonalities will be explored, including understanding the specification, reviewing the product data sheets (the PDS) and the material safety data sheet (the MSDS), comprehending the industry standard relevant to the specific project, documenting hold or checkpoints, understanding paper trails, and taking responsibility for ethics on the job. Module Two also explores the critical differences in the two roles, including issues of authority, reporting, testing, and documentation (which again, depends on the scope of work and the specification). Another issue explored by this module is the management of nonconformities. Learning Outcomes At the completion of this module you should be able to: - Describe the differences between quality assurance and quality control - Describe the common duties of quality assurance and quality control personnel - Describe the purpose and content of a pre-job conference - Explain the purpose of an inspection procedure/plan - Explain the importance of ethics of inspection personnel Describe the Differences Between Quality Assurance and Control Quality control (QC) is performing necessary observations, testing and documentation that verifies the work performed meets or exceeds some minimum standard as required by the project specification. Quality control is the contractor’s responsibility. Quality control involves the routine and systematic inspection and tests that are conducted to verify that each phase of the work (hold point) is in compliance with the specification. Quality Assurance (QA) is defined as the process to verify that the quality of work performed is actually what was reported by quality control. Quality assurance is typically performed by the owner (e.g. facility project engineer) or a third party on behalf of the Owner. Describe the Common Duties of Quality Assurance and Control Personnel Hold point inspections are typically done at: 1. Pre-cleaning 2. Surface Preparation 3. Primer Application 4. Intermediate Coat Application 7
PCI Study Guide- October 2007 5. Top Coat Application 6. Cure QC inspection should occur first and any non-conforming items identified by QC should be corrected, re-inspected and accepted by the QC. The QA observations should only occur after the work (hold point) has been accepted by the QC. The QA should then verify that the work that the QC accepted meets the requirements of the specification. Describe the Purpose and Content of a Pre-job Conference The pre-job conference should provide a review for all parties on the organizational structure and representatives of each stakeholder. This should include the title and responsibilities of each person as well as their reporting relationship within the company or organization. The pre-job conference should summarize the contractor’s approach to the project including: schedule, location(s) of equipment, and manpower estimates. The pre-job conference should review the specification and sequence of work, address specification discrepancies, and discuss how QC and QA inspections will be coordinated and implemented. It should include discussion of preparation of test sections, if required; adequate lighting; inspector safe access; inaccessible areas; and other project-specific considerations. The final phase of the pre-job conference should include a discussion of all required QC and QA documentation and submission schedules. The Owner should also address the procedure that should be followed if there are discrepancies in the QC and QA documentation. Explain the Purpose of an Inspection Procedure/Plan Project specifications can often be complex and contain many details unrelated to surface preparation and painting. As a result, locating the inspection check points can be cumbersome and time consuming. More consequential, key inspection checkpoints may be overlooked. The development of an inspection procedure before the project begins can aid the inspector in identifying the inspection checkpoints and the associated acceptance criteria. Explain the Importance of Ethics of Inspection Personnel Ethics is defined as “motivation defined by the ideas of right and wrong.” The legal definition of ethics is “of or relating to moral action and conduct; professionally right; conforming to professional standards.” Regardless of whether the coating inspector is functioning as QC or QA, the inspector must have a high level of personal integrity and a strong work ethic to provide quality monitoring of the project and a fair accounting to all involved parties. The inspector should not impose personal standards of quality or work, and must remain constantly aware that the criteria for work acceptance are the specification requirements. 8
PCI Study Guide- October 2007 Module Two: The Role of Quality Assurance (QA) and Quality Control (QC) Inspection Personnel on a Coating Project Workshop: Ethics As a group, review each of the scenarios below and discuss and answer the questions. Have a group spokesperson prepared to discuss your group’s answers at the end of the session. SCENARIO 1: You are performing part-time third party Quality Assurance services for the Owner. The contractor blast cleaned and painted while you were not on-site. When you arrive on-site, the Owner hands you a piece of paper that says “Tuesday, surface preparation OK. Ambient OK 100 gallons primer applied, OK.” He asks you to record this information on a dated inspection report and to sign it. Question 1: Do you record the information? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Question 2: If yes, how do record it “ethically?” _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Question 3: If no, what action(s) should you take? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ SCENARIO 2: You are hired by a Facility Owner to provide third party QA. You’ve been assigned to go out-of-town and are living in the same hotel as the contractor’s workers. You often see them in the hotel bar. Every time you are at the bar, the contractor pays for your drinks. Question 1: Is it okay to accept the “free” drinks? _________________________________________________________________________________ _________________________________________________________________________________ 9
PCI Study Guide- October 2007 _________________________________________________________________________________ Question 2: If no, how might you prevent this from occurring or handle it ethically? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ SCENARIO 3: The coating manufacturer is on-site passing out free hats. Question 1: Is it okay to accept the “free” hat? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ SCENARIO 4: You’ve been working as the Facility Owner’s QA on the same out-of-town project with the same contractor for over a year. You have a good working relationship. Your vehicle breaks down and you cannot replace it. The contractor allows you to use the company pick-up truck. He also gives you his credit card to use for gas. Question 1: What are the potential risks to this arrangement? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Question 2: List 3 potential ethical breaches related to this scenario: _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ SCENARIO 5: You are the contractor’s QC. You measure the ambient conditions prior to the start of painting with an epoxy primer and they comply with the specification. However, during painting you notice that the weather is changing and obtain additional ambient measurements that indicate the dew point temperature has now fallen below the surface 10
PCI Study Guide- October 2007 temperature. You advise the foreman, who tells you that his application is underway and that he’s going to finish painting, regardless of the conditions. He tells you to ignore it, to not record the additional measurements, and just let him finish the job. Question 1: Should you record the conditions? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Question 2: If yes, what then? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Question 3: If no, why? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________ Question 4: What other actions should be taken by the QC? _________________________________________________________________________________ _________________________________________________________________________________ _________________________________________________________________________________
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PCI Study Guide- October 2007 Module Two: The Role of Quality Assurance (QA) and Quality Control (QC) Inspection Personnel on a Coating Project Quiz 2 1. _________________ ___________________ is performing observations and tests, and documenting that the work meets/exceeds the specification requirements. 2. ________________ ____________________ is the contractor’s responsibility. 3. ________________ ____________________ is the process to verify the quality of work performed as reported by quality control personnel. 4. ________________ ____________________ is performed by the ______________ or a ________________ _____________________ on behalf of the __________________. 5. When an _______________ performs QA with his direct staff, he has a ______________________ _________________________ with the contractor and can exert control. 6. When an _____________ __________ performs QA for the owner, he does not have ______________________ _________________________ with the contractor and can only _________________ and document, and advise the __________________ QC. 7. Independent of whether _________________ ______________ personnel are on-site, the contractor remains responsible for __________________ _____________________. 8. When work is halted for an inspection, it is known as a __________ _____________ inspection. 9. List six common hold point inspections: _________________________________ _________________________________ _________________________________ _________________________________ _________________________________ _________________________________ 10. Which party should inspect the completed work first, QA or QC? ______________ 11. If the inspected area is deficient, which party should inspect the surface first after the rework is completed, QA or QC? _____________________ 12. ________ observations and test results typically supersede those of __________. 13. Prior to a pre-construction conference an inspector should ______________ the ______________________________.
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PCI Study Guide- October 2007 14. List seven topics that should be discussed at a pre-construction conference: _________________________________ _________________________________ _________________________________ _________________________________ _________________________________ _________________________________ _________________________________ 15. An inspection plan can contain three columns, titled as: _________________________________ _________________________________ _________________________________ 16. The content of the “acceptance criteria” section for an inspection plan comes from the _________________________________ 17. A Work Plan should cover the individual _________________ of a project, including both _________________________ and ___________________________. 18. A Work Plan is also known as a ____________________ ____________________ _____________________________. 19. One of the most important responsibilities of a coatings inspector is to ______________ the results of _______________________. 20. Fraudulent documentation, falsification of time/expense reports and acceptance of gifts in exchange for lenient inspection are ________________ ________________.
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PCI Study Guide- October 2007 Module Two: The Role of Quality Assurance (QA) and Quality Control (QC) Inspection Personnel on a Coating Project Supplemental Reading - Planning and Specifying Industrial Protective Coating Projects (SSPC Item #04-10) - The Inspection of Coatings and Linings: A Handbook of Basic Practice for Inspectors, Owners, and Specifiers, 2nd Edition (SSPC Item #03-14) - Coating and Lining Inspection Manual (SSPC Item #91-12)
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PCI Study Guide- October 2007 Module Three: Surface Preparation- Methods, Industry Standards and Inspection Module three explains the inspection of surface preparation. Inadequate surface preparation may be the most costly phase of a coating operation, and it is always critical to the project’s success. Surface preparation has a major focus in this training program, which covers in detail common standards used throughout the industry. The initial phase of pre-surface preparation and the inspection hold points are covered first, detailing the problems of weld spatter, edges, and repair areas. SSPC: The Society for Protective Coatings has developed a series of consensus standards to govern the surface cleanliness requirements. Currently, there are thirteen consensus standards for surface preparation. Each of these standards will be explored, including descriptions of what must be removed from the surface and what may remain on the surface for each standard. In addition to the surface preparation standards, the training will also focus on means and methods, including: blast cleaning equipment, a variety of abrasives, wet and dry abrasive blast cleaning, centrifugal blast cleaning, vacuum blast cleaning, hand and power tools, and waterjetting. The final focal points for Module Three are the common inspection checkpoints for surface preparation and the methods used to verify adherence to the specification. Learning Outcomes At the completion of this module you should be able to: - Describe the importance and dual objective of proper surface preparation - Define the SSPC, NACE, and ISO standards for surface preparation - Describe common methods used to prepare surfaces for coating - Describe methods used to control an environment during surface preparation activities - Measure and record surface profile - Evaluate surface cleanliness Describe the Importance and Dual Objective of Proper Surface Preparation The purpose of surface preparation is two-fold: to clean and to roughen the substrate according to the requirements of the specification. Sometimes the methods used to prepare surfaces for coating application achieve these criteria simultaneously (as with abrasive blast cleaning), while other times these steps must be performed separately (as with chemical stripping). In either case, the inspector must treat these as two distinct “acceptance criteria,” as the level of cleaning may be adequate, but the roughness may be insufficient or excessive. Alternatively, the surface roughness may be on target, but the level of cleaning may be inadequate. Define the SSPC, NACE, and ISO Standards for Surface Preparation The SSPC, NACE and ISO surface cleanliness standards prescribe a minimum acceptable level of cleaning, depending upon the specified degree of cleanliness required. The standards are known as “consensus documents” that are created by industry experts for inclusion in coatings specifications. They are not laws or regulations, but they become “contract law” once they are invoked in a specification for a coatings project. There are currently thirteen SSPC surface cleanliness standards. SSPC and NACE have jointly 15
PCI Study Guide- October 2007 published seven of them; SSPC is the sole publisher of the remaining six. The written standards for surface cleanliness are contained in Volume 2 of the SSPC Painting Manual, “Systems and Specifications” and are available for individual download from www.sspc.org. ISO currently has seven surface cleanliness standards. These standards define the level of cleaning required, and many of them are accompanied by visual guides that an inspector can use to verify that the minimum level of cleaning has been achieved. Describe Common Methods used to Prepare Surfaces for Coating Surface preparation methods employed by a painting contractor or facility owner can range from simple solvent cleaning to hand and power tool cleaning, dry and wet abrasive blast cleaning, chemical stripping, waterjetting and other more non-traditional methods such as sponge jetting and cryogenic blast cleaning using dry ice pellets. The degree of cleaning required by a given project specification is dependent on the service environment (the environment the coating must perform in), the coating system and the intended service life of the coating once installed. Describe Methods used to Control an Environment During Surface Preparation Activities The measurement of air temperature, relative humidity, dew point temperature, and surface temperature is usually associated with coating application. However, if the air temperature and relative humidity are such that moisture from the air condenses on the surface during final surface preparation, the surface may flash rust. Therefore, it is important to verify that the temperature of the surface is at least 3°C (5°F) higher than the temperature of the dew point, to preclude airborne moisture from condensing on the surfaces. These values (surface temperature and dew-point temperature) can be obtained using sling or battery-powered psychrometers in conjunction with US Weather Bureau Psychrometric Tables and surface temperature thermometers, or can be obtained using direct read-out electronic psychrometers equipped with surface temperature probes. The step-by-step use of this instrumentation is described below. It is important that the inspector not rely on prevailing weather conditions from a local service (e.g., airport weather station) as conditions at the project site and the specific work area can vary considerably. Ambient conditions should be measured and recorded prior to initiating final surface preparation and at 4-hour intervals thereafter, unless conditions appear to be declining. In this case, more frequent checks may be required. If surface preparation work will be done inside a facility, tank or inside of a containment, then the prevailing ambient conditions inside of the areas (at the actual location of the work) should be assessed. The location, date, time of day and the condition of air temperature, relative humidity, dew-point temperature and surface temperature should be recorded. However, since the only operation being monitored is surface preparation, the dew point/surface temperature relationship is most critical. Typically, there is no specified range for air temperature and relative humidity during surface preparation operations.
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PCI Study Guide- October 2007
Measure and Record Surface Profile Surface profile is defined as the average peak-to-valley depth that is generated by abrasive impacting the surface at high speed and by the impact created using certain power tools. By imparting a profile, the surface area is increased, enhancing the adhesion of the coating system to the surface. While an insufficient surface profile depth may result in poor coating system adhesion, excessive surface profile may cause pinpoint rusting and will require significantly more coating to fill all of the “valleys” of the surface profile and provide the specified thickness of coating above the “peaks” of the surface profile. Therefore, compliance with the minimum and maximum specified surface profile depth is critical to the success of a coating system. Factors affecting the depth of the surface profile include (for abrasive blasting) the type, hardness and size of the abrasive media employed, as well as the hardness of the surface being prepared. Lesser factors include the distance from the blast nozzle to the surface. For power tool cleaning, the type of tool and the configuration of the “impactors” will oftentimes dictate the depth of the surface profile. Adjusting to changes in profile depth requirements in specifications is best achieved by selecting a different sized abrasive. For projects requiring a relatively shallow surface profile depth, a smaller abrasive should be selected. For projects requiring a relatively deep surface profile, a larger abrasive should be selected, but may be blended with a smaller abrasive to increase productivity. Because of the industry’s recognition of the importance of surface roughness characteristics (beyond average surface profile depth), ASTM D7127, “Standard Test Method for Measurement of Surface Roughness of Abrasive Blast Cleaned Metal Surfaces Using a Portable Stylus Instrument” was published in 2005. The standard describes the procedures for verifying accuracy and using portable stylus-type instruments to obtain surface characterization data. An inspector may be required to perform peak count measurements in addition to peak-to-valley depth measurements (if required by the project specification). There are four industry-recognized standards for measuring surface profile, including ASTM D4417, “Test Methods for Field Measurement of Surface Profile of Blast Cleaned Steel;” NACE RP0287, “Field Measurement of Surface Profile of Abrasive Blast Cleaned Steel Surfaces Using a Replica Tape;” ASTM D7127 “Standard Test Method for Measurement of Surface Roughness of Abrasive Blast Cleaned Metal Surface Using a Replica Tape;” ASTM D7127 “Standard Test Method for Measurement of Surface Roughness of Abrasive Blast Cleaned Metal Surfaces Using a Portable Stylus Instrument.” These methods prescribe how to obtain measurements of surface profile depth and peak count, but do not provide an acceptance criterion (e.g., “the surface profile shall be 50-88 µm [2-3.5 mils…”]. Therefore, the project specification must indicate the desired surface profile depth and the minimum peak count (as required).
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PCI Study Guide- October 2007
Evaluate Surface Cleanliness There are four visual standards that have been developed for industry use by SSPC. To select the correct visual standard, simply ask yourself, “What does the project specification require regarding the method of surface preparation?” Then select from one of the four visual standards currently available: -
SSPC-VIS 1, “Guide and Reference Photographs for Steel Surfaces Prepared by Dry Abrasive Blast Cleaning,” SSPC-VIS 3, “Guide and Reference Photographs for Steel Surfaces Prepared by Power and Hand Tool Cleaning,” SSPC-VIS 4/NACE VIS 7, “Guide and Reference Photographs for Steel Surfaces Prepared by Waterjetting,” or SSPC-VIS 5/NACE VIS 9, “Guide and Reference Photographs for Steel Surfaces Prepared by Wet Abrasive Blast Cleaning.”
These visual standards are designed for use as guides. In the event of a dispute, it is the written surface cleanliness definitions that prevail. Also, the photographs in the standard will likely not provide an exact match to the surfaces prepared on your project, because the initial condition of the surface, the abrasive or tool employed, the surface profile, lighting and other factors can affect the appearance of the surface. Therefore the visual standards are truly designed as guides. In fact, many specifications now require the contractor to prepare a project specific cleanliness standard on the actual structure to be cleaned and coated. The project-specific standard represents the actual initial condition, the actual abrasive or tool employed, the surface profile depth and other jobsite conditions. The SSPC visual standards can be used during this process to establish the minimum acceptable cleanliness level for the specific project. Once established, this area can be preserved until the surface preparation portion of the project is completed.
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PCI Study Guide- October 2007
Module Three: Surface Preparation- Methods, Industry Standards and Inspection Workshop: Case Study
Surface Preparation of the Interior and Exterior of the Sun Spree Township Elevated Potable Water Storage Tank Project Description The Sun Spree Township Municipal Authority (a suburb of Ft. Lauderdale, FL) commissioned a coating condition survey of their 50 year old elevated potable water storage tank. The engineering firm’s report recommended total removal and replacement of the lining on the interior of the tank, as well as removal of the coating on the exterior of the tank, which contains both lead and chromium pigmentation in the existing coating. The exterior surfaces (underside of the bowl) also contain high levels of chloride (range of 50 to 100 µg/cm2), which is likely due to the proximity of the tank to the beach front. Sun Spree Township awarded the surface preparation and coating application work to Smith Bros. Contracting, a local QP1 certified firm that specializes in industrial surface preparation and painting. Smith Bros. is responsible for providing a trained specialist to perform quality control throughout the project. You are employed by Sun Spree Township as the resident corrosion specialist, and will be performing quality assurance oversight on the project. The information provided below was excerpted from the project specification and only pertains to surface preparation activities: Abrasive
Recyclable steel grit (conforming to SSPCAB 2 and AB 3)
Surface Cleanliness of Interior Surfaces
SSPC-SP 10/NACE No. 2
Surface Cleanliness of Exterior Surfaces
SSPC-SP 6/NACE No. 3
Cleanliness of Compressed Air
Per ASTM D 4285 (once/shift)
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PCI Study Guide- October 2007
Minimum Blast Nozzle Pressure
758 KPa (110 psi)
Surface Profile of Interior and Exterior Surfaces
Angular; 50-87.5 microns (2-3.5 mils); Minimum peak count: 34/cm
Minimum Lighting for Surface Preparation
500 Lux (47 foot-candles)
Minimum Lighting for Inspection
2000 Lux (186 foot-candles)
Environmental Conditions
Surface temperature a minimum of 3°C (5°F) above dew point
Maximum Surface Contamination Levels-Interior
Per SSPC-SP12; Level NV-1
Maximum Surface Contamination Levels-Exterior
Per SSPC-SP12; Level NV-2
Surface Dust Quantity Rating
1
Surface Dust Size Rating
2
Maximum Time Between Surface Preparation and Primer Application
8 hours
Work together in your teams to address each of the quality-related issues described below. Elect a team spokesperson to present your answers to the class and be prepared to defend them if questioned.
1. As the quality assurance inspector, how would you determine whether the abrasive the contractor has mobilized on the project site conforms to SSPC-AB3? 20
PCI Study Guide- October 2007
2. The contractor spent extra time preparing the exterior surfaces, and even exceeded the specified level of cleanliness (approached level SSPC-SP 10). However, the surface began to rust bloom before the primer could be applied. By coincidence, the amount of rust bloom did not exceed 33% of the surface. The contractor is claiming that the surface meets the minimum level of cleanliness required by the specification and wants to proceed with primer application. The surface preparation-to-primer application time is within the 8-hour window. Explain how you would respond.
3. The cleanliness of the compressed air was assessed by the quality control specialist upstream of the moisture and oil extractor. Comment as to whether this test was performed properly.
4. The blast nozzle pressure was reportedly measured by the quality control specialist before production blast cleaning was initiated and was recorded as 862 KPa (125 psi). During production abrasive blast cleaning, you ask the quality control specialist to re-measure the blast nozzle pressure, and the gage read 620 KPa (90 psi). Based on this information, answer the following: Does the “during production” pressure reading conform to the specification?
What may be causing the difference in the two pressures? 5. The interior steel surfaces of the tank contain pitting of the steel. Inspection of the surfaces after abrasive blast cleaning revealed trace amounts of paint residue in the bottom of the pits. However, the residue is only visible using a 10X illuminated magnifier. Is the presence of this residue cause for re-blasting of the surfaces?
6. The quality control specialist tested the condition of the recycled abrasive and recorded that the abrasive samples collected contained 2% of non-abrasive residue. Does the abrasive meet the requirement for non-abrasive residue under SSPC-AB2?
7. After 5 hours of production blast cleaning on the interior of the tank, the surface profile depth was measured by the quality control specialist and recorded as 107 µm (4.2 mils), with a peak count of 40/cm. 21
PCI Study Guide- October 2007
Does the surface roughness meet the requirements of the project specification?
If no, describe what steps the contractor may take to correct the non-conformity.
If no, describe what the contractor could have done to avoid the non-conformity.
8. The quality control specialist assessed the amount of light inside the tank prior to surface preparation operations. The amount of light was measured and recorded as 600 Lux (56 foot-candles).
Does this conform to the project specification?
The same amount of light was available when he assessed the surface cleanliness. Is this acceptable? Explain.
9. The quality control specialist measured the ambient conditions and surface temperature prior to abrasive blast cleaning. The surface temperature was 2°C (3ºF) above the dew point, but the conditions appeared to be improving, so the quality control specialist allowed the contractor to proceed. Was this acceptable? Explain.
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10. The quality control specialist reported the following levels after assessing the cleanliness of the exterior surfaces. Do the surfaces meet the requirements of the project specification?
Meets Specification CHEMICALChemi LLEVEL cal
Chloride
12 µg/cm2
Ferrous Ion
3 µg/cm2
Sulfate
None Detected
Yes
No
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PCI Study Guide- October 2007 Module Three: Surface Preparation- Methods, Industry Standards and Inspection Quiz 3 1. Preparing a surface for coating application is the most _________ and typically the most ____________________ step. 2. List five common responsibilities of a coatings inspector relating to surface preparation: ______________________________ ______________________________ ______________________________
___________________________ ___________________________
3. The two-fold purpose of surface preparation is to _________________ and ____________________the substrate. 4. ____________________and ____________________have prepared a standard and a recommended practice for measurement of ____________________. 5. ____________________dictates the required surface profile depth. 6. The surface profile or anchor pattern must be ____________________ with the entire ____________________. 7. List two “fabrication defects” that may be addressed in a coating specification. ____________________ ____________________ 8. List three methods that can be used to inspect surfaces for the presence of grease/oil: ____________________ ________________ ____________________ 9. ____________________occurs between mating surfaces, while ____________________forms on the surface of the steel. 10. Chemical contaminants like chloride trapped beneath a coating film can cause ____________________blistering, ____________________and ____________________failure. 11. Testing for chemical contamination involves two steps: ____________________ and ____________________. 12. ____________________environments are more conducive to coating deterioration caused by chemical contamination beneath the coating film than ____________________ environments.
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PCI Study Guide- October 2007 13. Suggested thresholds for soluble salt concentrations are found in the appendix to _____________________________________________. 14. The depth and shape of the surface profile generated by abrasive blast cleaning is determined by the ____________________and the ____________________ of the surface. 15. Abrasives fall into two general categories, ____________________ and ____________________. 16. SSPC AB 1 categorizes abrasives according to ____________________, ____________________and ____________________. 17. The abrasive cleanliness requirements in SSPC abrasive specifications AB1, AB2 and AB3 are ____________________requirements of the SSPC abrasive blast cleaning surface cleanliness standards. 18. List four tests that an inspector can perform in the field to verify conformance to SSPC AB1: ______________________________ ___________________________ ______________________________ ___________________________ 19. SSPC AB2 governs the quality of ____________________. 20. Steel grit produces an ____________________-shaped surface profile. 21. Steel shot produces a ____________________-shaped surface profile. 22. List three tests that an inspector can perform in the field to verify conformance to SSPC AB3: ______________________________ ___________________________ ______________________________ 23. List one test that an inspector cannot perform in the field to verify conformance to SSPC AB2: ____________________. 24. The diameter of an S330 steel shot abrasive is ____________________. 25. Which abrasive is larger, G25 or G50? ____________________. 26. Centrifugal blast machines often incorporate a blend of ____________________and ____________________abrasives. 27. Wet abrasive blast cleaning is used when ____________________must be controlled.
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PCI Study Guide- October 2007 28. High pressure water jetting incorporates pressures from _______ to _____ MPa. 29. Chemical strippers do not remove ____________________or ____________________and will not generate a ____________________. 30. Three methods used to prepare concrete for coating include: ______________________________ ___________________________ ______________________________ 31. SSPC surface cleanliness standards become contract law once they are invoked by the ___________________. 32. SSPC-SP1, “___________________” is an ___________________requirement of the SSPC surface cleanliness standards. 33. SSPC-SP2 “___________________” requires the removal of all ___________________& ___________________. 34. SSPC-SP2 requires the use of a ___________________as the inspection tool. 35. SSPC-SP3 “___________________” requires the removal of all ___________________mill scale, rust & ___________________. 36. What is the primary difference between SSPC-SP15, “___________________” and SSPC-SP11, “___________________?” _____________________________________________________. 37. In addition to solvent cleaning ___________________is an indirect requirement of SSPC-SP3, SP15 and SP11. 38. Which two SSPC surface cleanliness standards invoke a minimum surface profile requirement? ___________________and ___________________ What is the minimum requirement? ___________________ 39. List three possible “indirect requirements” of the SSPC abrasive blast cleaning standards: ______________________________ ___________________________ ______________________________ 40. The amount of staining allowed by the SSPC abrasive blast cleaning standards is based on what area? __________________
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PCI Study Guide- October 2007 41. SSPC-SP___/NACE No. 4, “__________________” requires the removal of all __________________rust, paint & mill scale. 42. SSPC-SP14/NACE No. ___, “___________________Cleaning” allows up to ___% ___________________ rust, paint or mill scale to remain. The amount of staining is ___________________. 43. The only difference between SSPC-SP ___/NACE No. 3, “___________________” and SSPC-SP10/NACE No. ___, “___________________” is ____________________________. 44. SSPC-SP___/NACE No. 3 allows up to ___% staining to remain on each ___ square inch area. 45. SSPC-SP10/NACE No. ___ allows up to ___% staining to remain on each ___square inch area. 46. SSPC-SP___/NACE No. ___allows no paint, rust, mill scale or straining to remain. 47. SSPC-SP___/NACE No. ___, level WJ-2 allows up to ___% of the surface to contain straining or tightly adhering matter. 48. The “L” in “SSPC SP12-WJ-3-L” indicates ______is permitted by the specification. 49. ISO St2, “___________________” requires removal of all ___________________materials. 50. ISO ___, “___________________” allows only stains to remain on the surface. 51. The SSPC/NACE and ISO cleanliness standards prohibit the use of ___________________ when inspecting surface cleanliness. 52. Prior to final surface preparation, it is recommended that the inspector verify that the ___________________ temperature is at least ___oF (___oC) higher than the ___________________ temperature. 53. Dehumidification equipment ___________________ moisture from the air. 54. List three methods of dehumidification: ___________________, ___________________, ___________________.
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PCI Study Guide- October 2007 55. Cooling air below the dew point for dehumidification of the air is the ___________________ method. 56. Products that absorb moisture from the air as a means of dehumidification use the ___________________ method. 57. Indicate the procedure for conducting a compressed air cleanliness test, below: Conduct the test ___________________ stream of ___________________ and oil separation. Position the air outlet ___” from the collector Exhaust the compressed air onto the collector for approximately ______. 58. To conduct a “vial test,” fill a clear container with ___abrasive and an equal amount of ___________________. Allow the shaken blend to settle for ___________________. 59. The maximum abrasive conductivity according to the SSPC abrasive specifications is ___ µS. 60. The minimum level of lighting for inspection is ___ Lux. 61. The recommended level of lighting for inspection is ___ ft/candles. 62. The visual standard reference “G2 SP14” in SSPC VIS 1 indicates: ___________________________________________________. 63. The visual standard reference “F SP3 PWB” in SSPC VIS 3 indicates: ______________________________________________________ 64. The visual standard reference “D WJ3 M” in SSPC VIS 4/NACE VIS 7 indicates: __________________________________________________________ 65. The visual standard reference “C WAB 6 H” in SSPC VIS 5/NACE VIS 9 indicates: _______________________________________________ 66. The visual standard reference “A Sa3” in ISO 8501-1:1988 indicates: __________________________________________________ 67. Surface profile is defined as the maximum ___________________depth. 68. Profile generation ___________________ the surface area of the steel. 69. An increase in peak count reportedly enhances ___________________and a greater resistance to ___________________. 70. The ___comparator disc is selected for inspection of surface profile when garnet abrasive is used to perform abrasive blast cleaning. 28
PCI Study Guide- October 2007
71. “3.0SH76” on a comparator disc segment indicates: ___________________. 72. Verify “zero-set” on a surface profile depth micrometer using a ___________________. 73. The measuring range of X-Coarse replica tape is ___mils. 74. The thickness of the Mylar film on replica tape is ___ mils. 75. Each grade of replica tape is most accurate in the ___ of the range. 76. Complete the following chart: Parts Per Million Chloride Amount of Extraction Liquid Micrograms of Chloride Area Extracted Micrograms per cm2 chloride
176 2 mL ___ 12.25 cm2 ___
77. Complete the following chart: Conductivity of sample Conductivity of blank Net Conductivity of sample
120 µS/cm 8.7 µS/cm ___
78. Convert 35 µS/cm to surface chloride concentration using the formula on Page 3-147. ___________________ 79. A pH of 10 is considered ___________________. 80. A pH of 3 is considered ___________________.
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PCI Study Guide- October 2007
Module Three: Surface Preparation- Methods, Industry Standards and Inspection Supplemental Reading List -
Good Painting Practice: SSPC Painting Manual, Volume 1, 4th Edition (SSPC Item #02-14)
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Systems and Specifications: SSPC Painting Manual, Volume 2, 2005 Edition (SSPC Item #04-13)
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Surface Preparation Specifications and Practices (SSPC Item #05-03)
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SSPC-VIS 1 Guide and Reference Photographs for Steel Surfaces Prepared by Dry Abrasive Blast Cleaning (SSPC Item #02-12)
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SSPC-VIS 3 Guide and Reference Photographs for Steel Surfaces Prepared by Hand and Power Tool Cleaning (SSPC Item #04-07)
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SSPC-VIS 4 Guide and Reference Photographs for Steel Surfaces Prepared by Waterjetting (SSPC Item #01-05)
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SSPC-VIS 5 Guide and Reference Photographs for Steel Surfaces Prepared by Wet Abrasive Blast Cleaning (SSPC Item #01-06)
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PCI Study Guide- October 2007
Module Four: Practical Arithmetic for the Coatings Inspector Module Four reviews practical math skills used by the coatings inspector. Coating inspectors frequently need to apply basic math skills to everyday inspections. This module provides a review of common arithmetic associated with coatings inspection, including: converting percentages to decimal format; calculating square footages; calculating volume and converting ounces/gallon to percentage of thinner addition; converting VOC values; converting temperatures; and converting units of measurement for surface profile depth and paint thickness (mils to microns and back). A special session on calculating coating material quantities based on theoretical and practical coverage rates is included in this module. Learning Outcomes At the completion of this module you should be able to: - Apply practical arithmetic to calculations relating to everyday jobs Apply Practical Arithmetic to Calculations Relating to Everyday Jobs Arithmetic can be one of the more challenging aspects of coatings inspection that an inspector must employ on a project. Those challenged by mathematics simply throw up their hands and give up, rather than working through the formulas to generate the correct value(s), or they may rely on others to perform calculations for them. This module helps inspectors to become more comfortable with mathematics and describes the steps necessary to perform basic calculations. An inspector should always be equipped with a working calculator to make the calculations easier and faster, and to avoid making simple mathematical errors. Recognize however, that if an incorrect value (or the incorrect form of a value) is inadvertently entered into the calculator, the answer will be wrong despite using the correct formula. So take your time and double check all entries. The old phrase says “practice makes perfect” and replication helps. If you are unfamiliar with any of the mathematics described in this module, practice the examples over and over. You can even substitute your own numbers in the examples to help gain confidence in application of the formulas. Finally, recognize that there is always more than one way to arrive at the correct answer. This module describes commonly used methods, but other methods or procedures may be used, as long as the final answer is the same.
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PCI Study Guide- October 2007
Module Four: Practical Arithmetic for the Coatings Inspector Workshop: Arithmetic for Protective Coatings Inspector
Instructions Using the basic arithmetic skills taught in Module 4, solve each of the Problem Sets below. Remember to use your calculator to avoid making simple math errors. You may select the US standard or the metric exercises, depending on the prevailing system used. Problem Set 1: Averaging Values You have collected the following surface profile measurements. Calculate the average of each area, then average all of the areas together. Area 1 50 microns 75 microns 62 microns
Area 2 40 microns 43 microns 49 microns
Area 3 76 microns 80 microns 57 microns
Area 4 42 microns 58 microns 55 microns
Area 5 44 microns 71 microns 56 microns
Area 1 2 mils 3 mils 2.4 mils
Area 2 1.6 mils 1.7 mils 2 mils
Area 3 3 mils 3.1 mils 2.2 mils
Area 4 1.7 mils 2.3 mils 2.2 mils
Area 5 1.7 mils 2.8 mils 2.2 mils
Average of Area 1 Average of Area 2 Average of Area 3 Average of Area 4 Average of Area 5
______________ ______________ ______________ ______________ ______________
Average of all Areas _______________
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PCI Study Guide- October 2007
Problem Set 2: Averaging Values You have collected the following coating thickness measurements. Calculate the average of each area, then average all of the areas together. Area 1 205 microns 312 microns 199 microns
Area 2 181 microns 233 microns 241 microns
Area 3 305 microns 295 microns 287 microns
Area 4 256 microns 214 microns 277 microns
Area 5 311 microns 298 microns 283 microns
Area 1 8 mils 12.3 mils 7.8 mils
Area 2 7.1 mils 9.2 mils 9.5 mils
Area 3 12 mils 11.6 mils 11.3 mils
Area 4 10.1 mils 8.4 mils 10.9 mils
Area 5 12.2 mils 11.7 mils 11.1 mils
Average of Area 1 Average of Area 2 Average of Area 3 Average of Area 4 Average of Area 5
______________ ______________ ______________ ______________ ______________
Average of all Areas _______________
Problem Set 3: Converting Percentages to Decimal Format A two-coat exterior coating system has been specified and the products have been delivered to the project site. You have elected to calculate target wet film thickness and the maximum amount of thinner that can be added to each. The coating manufacturer lists the volume solids content and the allowable thinner as a percentage. You will need to convert each of the percentages to decimal.
Allowable percentage of thinner for the primer: Volume solids content of primer: Allowable percentage of thinner for the topcoat: Volume solids content of topcoat:
15% 65% 5% 52%
Decimal Format _____________ _____________ _____________ _____________
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PCI Study Guide- October 2007 Problem Set 4: Calculating Area A cylindrical ground storage tank contains four (4) shell rings. Each shell ring is made from eight (8) steel plates measuring 3 meters (10 feet) by 7 meters (23 feet). The interior and exterior of the tank is to be coated (excluding the interior floor and interior ceiling, and the exterior roof, which all appear to be in good condition). The tank owner has asked you to verify that the contractor has ordered enough coating, so you will need to first calculate the total area of the shell rings to be coated. Use the space below to show the steps you took to arrive at the final answer. Total area of shell rings to be coated:
________________
Show steps here:
Problem Set 5: Calculating Area The project specification for surface preparation of steel I beams in the fabrication shop requires three (3) surface profile measurements every 30 square meters (100 square feet) of prepared surface. There are two sizes of I beams on the project: Beam Size A: 0.5 meter (18 inch) flanges (2.54 cm [1 inch] thick) 2 meter (6 foot) web 18 meters (60 foot) beam length 12 – stiffeners, each 2 meters (6 foot) x 10 cm (4 inches) wide Beam Size B: 0.5 meter (18 inch) flanges (2.54 cm [1 inch] thick) 2.5 meter (8 foot) web 24 meters (80 foot) beam length 16 – stiffeners, each 2 meters (6 foot) x 10 cm (4 inches) wide Total square meters (square feet) for Beam Size A: ______________ Total square meters (square feet) for Beam Size B: ______________ If the total project involves 12 beams of Size A and 15 beams of Size B, now many surface profile measurements are required for the project? ___________________ 34
PCI Study Guide- October 2007
Use the space below to show the steps you took to arrive at the answers. You may also want to draw and label the two beams with the dimensions for each to help visualize the sizes.
Problem Set 6: Calculating Volume of Coating A three-component product has been selected for use on a project. Component A is 11 liters (3 gallons) in a 19 liter (5 gallon) container. Component B is 3.8 liters (1 gallon) in a 3.8 liter (1 gallon) container. Component C is 0.5 liter (1 pint) in a 1 liter (1 quart) container. What is the total volume of coating once all components are combined together?
Problem Set 7: Calculating Volume of Thinner According to the manufacturer’s product data sheet for the three-component coating in Problem Set 6, the coating must be thinned 15%. What is the total volume of thinner that must be added to the coating?
Problem Set 8: Converting Milliliters/Liter to Percentage According to the manufacturer’s product data sheet, the recommended amount of thinner to add to a coating is 50 milliliters per liter of coating. If the mixed volume of coating is 5 liters, how many milliliters of thinner will be added? What percentage of thinner will be added to the coating?
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PCI Study Guide- October 2007 Problem Set 9: Converting Ounces/Gallon to Percentage
According to the manufacturer’s product data sheet, the recommended amount of thinner to add to a coating is 13 ounces per gallon of coating. If the mixed volume of coating is 5 gallons, how many ounces of thinner will be added? What percentage of thinner will be added to the coating? Problem Set 10: Converting VOC Content The local air quality regulations for a recoating project do not allow coatings containing VOC in excess of 2.1 lbs./gallon. The product data sheet that the coating manufacturer provided for the solvent-borne primer only reports the VOC content in grams per liter, which is 250 grams/liter. Can the coating be used on the project?
Based on the VOC content reported on the product data sheet, will the contractor be able to thin the coating?
Problem Set 11: Converting VOC Content A steel fabrication shop that also performs surface preparation and primer application work is located in an area with very strict air pollution regulations. Coatings used by the fabrication shop cannot exceed 375 grams/liter VOC. The shop wants to use a primer that contains 3.9 lbs./gal. VOC. Can the primer be used by the shop?
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PCI Study Guide- October 2007 Problem Set 12: Converting Temperature According to the coating manufacturer’s product data sheet, the air temperature must be maintained between 40°F and 100°F during application. The air temperature is 34°C. Can coating application work continue? After answering yes/no, indicate the actual temperature in °F.
Problem Set 13: Converting Temperature According to the coating manufacturer’s product data sheet, the coating storage area must be maintained between 10°C and 49°C. The air temperature in the storage area is 125°F. Does the storage temperature conform to the manufacturer’s requirements? After answering yes/no, indicate the actual temperature in °C.
Problem Set 14: Converting Units Used to Express Coating Thickness and Surface Profile Depth The coating specification requires a 2.0-3.5 mil surface profile depth. The actual surface profile depth ranges from 63.5 to 83.8 microns. Does the area meet the specification? After answering yes/no, indicate the actual surface profile range in mils.
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PCI Study Guide- October 2007 Problem Set 15: Converting Units Used to Express Coating Thickness and Surface Profile Depth The coating specification requires the primer and intermediate coats to be a combined thickness of 203-305 microns. The thickness of the combined coats ranges from 6 to 10 mils. Does the area meet the specification? After answering yes/no, indicate the actual coating thickness range in microns.
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PCI Study Guide- October 2007 Problem Set 16: Calculating Coating Material and Thinner Requirements A three-coat system has been specified for protecting a structure estimated to be 2,323 square meters in area. The volume solids content is 75% for the primer, 56% for the intermediate coat and 46% for the topcoat. The specified thickness is 75-100 microns for the primer, 125-178 microns for the intermediate coat and 50-75 microns for the topcoat. The contractor will need to reduce the primer and intermediate coatings by 10% with Thinner No. 2 and will need to thin the topcoat by 5% using Thinner No. 4. Mixing and application losses are estimated to be 20% for each coating, and the surface profile is expected to consume 15% of the primer. Based on this scenario, complete the chart below: Inquiry
Enter Answer Here
Quantity of primer required (in liters) Quantity of intermediate coating required (in liters) Quantity of topcoat required (in liters) Quantity of thinner required for primer & intermediate coatings (in liters) Quantity of thinner required for topcoat (in liters)
Show the metric version of the formula for calculating coating coverage here:
Show the values/equations you used to arrive at each answer below.
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PCI Study Guide- October 2007 Problem Set 17: Calculating Coating Material and Thinner Requirements A three-coat system has been specified for protecting a structure estimated to be 25,000 square feet in area. The volume solids content is 75% for the primer, 56% for the intermediate coat and 46% for the topcoat. The specified thickness is 3-4 mils for the primer, 5-7 mils for the intermediate coat and 2-3 mils for the topcoat. The contractor will need to reduce the primer and intermediate coatings by 10% with Thinner No. 2 and will need to thin the topcoat by 5% using Thinner No. 4. Mixing and application losses are estimated to be 20% for each coating, and the surface profile is expected to consume 15% of the primer. Based on this scenario, answer the questions below: Inquiry
Enter Answer Here
Quantity of primer required (in gallons) Quantity of intermediate coating required (in gallons) Quantity of topcoat required (in gallons) Quantity of thinner required for primer & intermediate coatings (in gallons) Quantity of thinner required for topcoat (in gallons)
Show the US Standard version of the formula for calculating coating coverage here:
Show the values/equations you used to arrive at each answer below.
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PCI Study Guide- October 2007 Module Four: Practical Arithmetic for the Coatings Inspector Quiz 4 1. Average the following set of surface profile measurements: 3.5, 3.7, 2.9, 3.1, 4.0 _____________ 2. Convert 39% to decimal format.
_____________
3. Calculate the amount of thinner to add to 10 gallons of mixed coating to be reduced 20%. _____________ 4. Calculate the area of a square that is 4.5 feet x 13.6 feet. _____________ 5. Calculate the area of an I-beam that is 40 feet in length, has 12” wide flanges, a 48” web, and 8 stiffeners (4” wide x 48” long). _____________ 6. Calculate the exterior surface area of a tank that is 45 feet in height and 90 feet in diameter. _________________________________________________________ Calculate the volume of water the tank in Question 6 will hold. _________________________________________________________ 7. Convert 2.4 pounds/gallon VOC to grams/Liter. _____________________________________ 8. Convert 64oF to oC. ______________ 9. Convert 275 micrometers to mils _______________ 10. Calculate the quantity of primer required to coat 15,000 square feet of blast cleaned steel, based on the following data: Specified Dry Film Thickness: Volume Solids Content: Mixing/Application Loss Estimate: Surface Roughness Loss Estimate: Recommended Thinner Addition:
3-5 mils 84% 25% 20% One pint per gallon
_________________________________________________________
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PCI Study Guide- October 2007 Module Four: Practical Arithmetic for the Coatings Inspector Supplemental Reading List - Practical Math for the Protective Coatings Industry (SSPC Item #03-05)
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PCI Study Guide- October 2007 Module Five: Coating, Mixing, Thinning and Application: Equipment Overview and Inspection Techniques Module Five explains the inspection of coating mixing, thinning, and application. Experts claim that poor application, along with inadequate surface preparation, cause the majority of all industrial coating failures. This module provides an overview of the various methods used to apply coatings, including conventional (air) spray, airless spray, HVLP, air-assisted airless spray, and brush & roller. The advantages and limitations of each method, along with proper technique will be emphasized. Module Five will continue with the inspection of mixing, thinning, and coating application processes, including measuring ambient conditions, witnessing and documenting mixing and thinning procedures, wet and dry film measurements, use of the Tooke Gage (destructive testing) to determine the thickness of individual layers in a coating system, pinhole/holiday detection, adhesion, and coating hardness and curing tests. Learning Outcomes At the completion of this module you should be able to: - Describe the procedures associated with proper mixing, thinning, and application of industrial coatings - Define the SSPC standards for coating application - Describe the role of the coating inspector on a coatings project - Use MSDS and product data sheets to verify safe and proper mixing, thinning, and application of coatings - Describe the inspector’s role regarding coating material receipt and storage - Measure and record ambient conditions and surface temperature - Calculate Wet Film Thickness - Measure Wet Film Thickness - Verify accuracy of nondestructive coating thickness gages - Measure coating thickness using nondestructive gages - Describe the SSPC standard for measurement of coating thickness - Measure coating thickness using destructive methods - Detect pinholes and holidays - Measure coating adhesion - Evaluate coating cure - Measure coating hardness - Describe methods used to verify intercoat cleanliness Describe the Procedures Associated with Proper Mixing, Thinning, and Application of Industrial Coatings Proper coating mixing procedures are one of the most important steps in the successful installation of a protective coating system. The procedures for blending single component materials is straightforward and needs little instruction other than ensuring the material is homogeneous by mixing all of the settled pigment and solids materials into the liquid. Conversely, the mixing procedures for multiple component materials can be more complex, and often requires the individual responsible for mixing the coatings and the inspector to read and comprehend the product data sheets. 43
PCI Study Guide- October 2007
Similar to mixing, thinning of a coating material is perceived to be rather straightforward and requires little explanation. However, the type and amount of thinner added to the coating impacts the volatile organic compound (VOC) content, the target wet film thickness of the coating, and over thinning or under thinning a coating can adversely affect the application and performance characteristics. Therefore, thinning of a coating is an important area to discuss and is equally important to verify that it is done properly. Transferring the coating materials from the can to the surface can be accomplished in a number of ways. Factors that should be considered when deciding on an application method include the size and configuration of the surfaces to be coated, the desired or required transfer efficiency, the type of coating, environmental regulations, the proximity to other operations/conditions, the specification and the coating manufacturer’s recommendations. The seven methods of coating application that we will describe in this module include: 1. Brushes, rollers, and daubers 2. Airless spray 3. Conventional (air) spray 4. High Volume Low Pressure (HVLP) spray 5. Air-assisted airless spray 6. Metallized spray 7. Plural component spray Define the SSPC Standards for Coating Application SSPC has two main standards that pertain to coating application, including SSPC PA 1 (Shop, Field and Maintenance Painting of Steel) and SSPC PA 2 (Measurement of Dry Coating Thickness with Magnetic Gages). Describe the Role of the Coating Inspector on a Coatings Project The inspector’s role in a coating project varies, depending on the requirements of the specification. The more common checkpoints include: 1. performing materials receipt inspection and documentation 2. witnessing and verifying (documenting) coating mixing and thinning procedures 3. measuring and documenting ambient conditions and surface temperature 4. calculating and measuring wet film thickness 5. measuring dry film thickness nondestructively 6. verifying re-coat times 7. assessing intercoat cleanliness 8. assessing cure 9. assessing coating hardness 10. performing pinhole or holiday detection 11. adhesion testing
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PCI Study Guide- October 2007 Use MSDS and Product Data Sheets to Verify Safe and Proper Mixing, Thinning, and Application of Coatings Coating manufacturers technical bulletins or product data sheets (PDS) contain very useful information about the products being used on the project. However, the manufacturer is not limited to which product information they may or may not reveal. While the PDS typically contains critical information about the content and use of the coating products, in cases where the PDS and the specification differ (say on the maximum humidity during application), the specification is the governing document, except when the owner incorporates the manufacturer’s recommendations on the PDS into the specification. When that occurs, the PDS becomes part of the project specification. Describe the Inspector’s Role Regarding Coating Material Receipt and Storage Verifying that what was ordered (coating products, coating components, and thinners, if permitted) was received at the project site in good condition and in the correct amounts is called a material receipt inspection. This is typically a job for the contractor’s QC and although it is not a difficult process, it can prevent a multitude of problems as the job moves forward. The contractor should also verify that the coating products are properly stored on the project site prior to use, and should record batch no’s. for each component and thinner. Measure and Record Ambient Conditions and Surface Temperature Prior to the mix and throughout the application process, the measurement of ambient conditions (relative humidity, dew point, air temperature, wind conditions) helps determine whether the application of the coating can move forward. Often, both the specification and the PDS will contain information on the conditions required to apply each specific coating product. If the requirements listed in the project specification differ from that listed on the PDS, the specification is the governing document. The right weather conditions for the coating products open the way to a successful application of the coating. If a coating must have moisture to cure, too little moisture in the air becomes a problem. Conversely, for some coatings, too much moisture in the air creates a problem. Warm versus cold air temperature ranges are also important issues. And wind conditions are important, especially in areas where strong winds are frequently a problem. Ambient conditions should be measured at regular intervals both before and throughout the application process, and anytime the weather conditions appear to be changing. Perhaps the single most important temperature relationship is the relationship between the dew point and the surface temperature. To prevent applicators from coating a “wet surface”, the surface temperature should be at least 3°C (5°F) higher than the dew point temperature. An inspector should not depend on national or regional weather service information for weather conditions. Conditions must be measured at the correct time at the exact location where the coating application will take/ is taking place.
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PCI Study Guide- October 2007 Calculate Wet Film Thickness Some coating manufacturers list the target wet film thickness, while others do not. But even when the targeted wet film thickness is listed on the PDS, this thickness will change if the thinner is added to the product, or when the specified dry film thickness differs from that on the PDS. It is important for contractors and inspectors to know how to calculate the target wet film thickness, in order to arrive at the desired dry film thickness. There are two formulas that can be used to calculate wet film thickness; one for unthinned coatings and one for coatings that is reduced. The volume solids content of the coating and the percentage of thinner added to the coating must be known in order to calculate a wet film thickness. Measure Wet Film Thickness Measurement of wet film thickness is typically performed by the applicator, although an inspector should spot-check and record the measured wet film thickness. A notch-type wet film thickness gage can be used for this purpose. Verify Accuracy of Nondestructive Coating Thickness Gages All coating thickness gages, whether Type 1 (magnetic pull-off) or Type 2 (electronic), must be verified for accuracy before and after each period of use. Typically, calibration blocks are used to verify the accuracy of magnetic pull-off gages, while plastic shims are used to verify electronic gages. However, the inspector should always check the specification to determine which type of gage to use and the method to verify the gage’s accuracy. Surface profile or roughness affects dry film thickness gages. If a gage is verified for accuracy on smooth steel blocks (and the coating will be applied to roughened steel) the amount the gage is affected (called the Base Metal Reading or BMR) must be measured and deducted from each cumulative coating layer. If a gage is verified for accuracy by placing shims of known thickness on top of the peaks of the roughened steel (the same surface the coating will be applied to), then there is no BMR to measure or deduct. Measure Coating Thickness Using Nondestructive Gages While the applicator is concerned with the wet film thickness of the applied coating, inspection personnel are much more concerned with the end result, or the dry film thickness. The measurement of wet film thickness is simply a means to an end on most metal surfaces where measurement of the dry film is feasible. Currently there are three standards that address the nondestructive measurement of coating thickness: SSPC PA 2 (2004), “Measurement of Dry Coating Thickness with Magnetic Gages;” ASTM D 709105, “Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals;” and ASTM D 6132, “Standard Test Method for Nondestructive Measurement of Dry Film Thickness of Applied Organic Coatings over Concrete Using and Ultrasonic Gage.” Each of these standards prescribes methods for verifying the accuracy of the measuring devices and for obtaining coating thickness measurements.
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PCI Study Guide- October 2007 Aside from the industry standards, coating thickness measurements should be obtained after the application of each coat in a multiple coat system, not just after the final coat. The vast majority of nondestructive coating thickness gages described in SSPC-PA 2 and ASTM D7091 cannot distinguish individual coating layers, but rather measure the total “gap” between the substrate and the gage probe. Describe the SSPC Standard for Measurement of Coating Thickness Frequency of dry film thickness measurements is another inspection concern. Both ASTM D 7091 and SSPC PA 2 have specific requirements for the number of readings that are taken and the number of areas measured according to the size of the structure. SSPC PA 2 requires obtaining a minimum of three gage readings at each spot. These gage readings are averaged to create a spot measurement and there is no restriction placed on the individual gage readings (relating to thickness tolerance). SSPC PA 2 places a tolerance on the five spot measurements that comprise an area measurement. The spot measurements must be within 80% of the minimum specified thickness and 120% of the maximum specified thickness. The average of the five spot measurements (the area measurement) must fall within the specified thickness range established by the project specification. Measure Coating Thickness Using Destructive Methods Once all the coatings of a multi-coat system have been applied, the only way to assess the thickness of each coat is through the use of a Tooke Gage. The Tooke Gage cuts a groove through the coating layers all the way down to the substrate using one of three precision cutting tips. By using the microscope on the gage, an inspector can examine the coating to determine the thickness of each layer. The Tooke Gage can be used to examine different or alternating colored layers in a multi-coat system up to 50 mils thick. Detect Pinholes and Holidays Some coatings must perform in very challenging service environments: for example, the coatings applied to the interior of storage tanks, railcars, and liquid and gas pipelines. Visual inspection of these coatings for pinholes, skips, or missed areas would not be adequate, therefore holiday or pinhole detectors are used to determine the location of skips, misses, and pinholes. This testing is performed so coating or lining can be repaired before the vessel is put into service. Holidays are skips or misses in the coating system. Pinholes are tiny voids in the coating that penetrate all the way to the substrate. The type of pinhole detection employed (low or high voltage) is based on the coating system thickness. This type of inspection can only be performed on nonconductive coatings applied to electronically conductive substrates. In general, the test voltage for high voltage holiday detection is 100-125 volts/25µm (1 mil); however, the manufacturer of the coating system should provide the proper test voltage. Measure Coating Adhesion Some specifications require the measurement of the adhesion of the applied coating system after it has cured. Adhesion assessments may include: the adhesion of the coating to the substrate, the adhesion or the bond of one layer of the coating to another, or the inner-strength of the coating, also known as cohesive strength. 47
PCI Study Guide- October 2007 Different adhesion tests measure different coating adhesion mechanisms (peel back versus pull-off). Two tests that are common for the field are the “Adhesion by Tape Test” (ASTM D3359) and the “Knife Adhesion Test” (ASTM D6677). These two tests are used to evaluate the coating’s “shear” or “peel” strength. The third test measures tensile strength and is governed by ASTM D 4541, “Pull-off Strength of Coatings Using Portable Adhesion Testers,” This test is used to evaluate the coatings resistance to a perpendicular force on a pre-attached pull stub. All adhesion testing is destructive to the coating film and should not be conducted unless required by the specification. The specification should include repair procedures for the affected areas. Evaluate Coating Cure The inspector may be required to verify that a coating has adequately dried or cured prior to application of subsequent coats, or prior to placing the coating system into service (i.e., filling up the tank/vessel). ASTM has three test methods for evaluating or assessing the degree of coating drying or curing. These methods include drying tests (set-to-touch, tack-free, dry-to-touch, dry-to-handle, dry-to-recoat, etc.) per ASTM D 1640 and two solvent rub tests (one for organic coatings [ASTM D 5402] and one for ethyl silicate type inorganic zinc-rich primers [ASTM D 4752]). Measure Coating Hardness The hardness of a coating can also be an indicator of the degree of cure, and an inspector may be required to test the hardness of the coating film using the pencil hardness test (ASTM D 3363), or an impressor/indenter test (Barcol hardness [ASTM D 2583] or Durometer hardness [ASTM D 2240]). Describe Methods Used to Verify Intercoat Cleanliness Airborne dirt and dust is common on industrial painting sites and may become deposited onto the coated surface. This poses no particular problem unless the surface is scheduled to be recoated. In this case, a visual or tactical (touch) examination of the surface is required to detect the presence of dust and to help prevent intercoat contamination. Alternatively, the pressure-sensitive tape procedure (ISO 8502, Part 3) can be used to assess the presence of dust on coated surfaces, in the same manner used for evaluating dust on prepared surfaces. Surface dust/debris can cause subsequent applied coatings to fisheye (inability to wet the surface) and, in sufficient quantities, can cause intercoat delamination.
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PCI Study Guide- October 2007 Module Five: Coating, Mixing, Thinning and Application: Equipment Overview and Inspection Techniques Workshop: Case Study
Project Description
The Sun Spree Township Municipal Authority (a suburb of Ft. Lauderdale, FL) commissioned a coating condition survey of their 50-year-old elevated potable water storage tank. The engineering firm’s report recommended total removal and replacement of the lining on the interior of the tank, as well as removal of the coating on the exterior of the tank, which contains both lead and chromium pigmentation in the existing coating. Sun Spree Township awarded the surface preparation and coating application work to Smith Bros. Contracting, a local firm that specializes in industrial surface preparation and painting. Smith Bros. is responsible for providing a trained specialist to perform quality control throughout the project. You are employed by Sun Spree Township as the resident corrosion specialist, and will be performing quality assurance oversight on the project. The interior of the tank has been prepared to achieve a “Near-White Metal” blast; the exterior has been blast cleaned to conform to SSPC-SP 6, “Commercial Blast.” Both surfaces are ready to be coated. The interior will be lined with a 3-coat NSF-approved epoxy system. The three coats will be tinted different colors, but the manufacturer and product no. are the same for each coat. The exterior will be coated with one coat of epoxy and two coats of polyurethane (color coat and clear coat with dissipative dye). The information provided below was excerpted from the project specification and only pertains to coating/lining system installation activities:
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PCI Study Guide- October 2007 Interior Lining Minimum Lighting for Coating Application
500 Lux (47 foot-candles)
Minimum Lighting for Inspection
2000 Lux (186 foot-candles)
Environmental Conditions
Air Temperature: 50-120°F Relative Humidity: Maximum 85% Surface Temperature: 50-120°F Surface Temperature a Minimum of 3°C (5°F) Above Dew Point
Mixing Requirements
Complete kits as supplied using a shear mixing blade
Thinning Requirements
Per manufacturer’s instructions
Coating Application Equipment
Airless Spray, per manufacturer’s instructions
Coating Thickness
SSPC-PA2
Primer Thickness
125-175 µm (5-7 mils)
Intermediate Coat Thickness
125-175 µm (5-7 mils)
Topcoat Thickness
125-175 µm (5-7 mils)
Stripe Coats
After primer application (using primer) After intermediate coat application (using intermediate coat)
Maximum Time Between Coats
30 Days
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PCI Study Guide- October 2007 Exterior Coating Minimum Lighting for Coating Application
500 Lux (47 foot-candles)
Minimum Lighting for Inspection
2000 Lux (186 foot-candles)
Environmental Conditions
Air Temperature: 50-120°F Relative Humidity: Maximum 85% Surface Temperature: 50-120°F Surface Temperature a Minimum of 3°C (5°F) Above Dew Point
Mixing Requirements
Complete kits as supplied using a shear mixing blade
Thinning Requirements
Per manufacturer’s instructions
Coating Application Equipment
Airless Spray, per manufacturer’s instructions
Coating Thickness
SSPC-PA2
Primer Thickness
125-175 µm (5-7 mils)
Intermediate Coat Thickness
75-100 µm (3-4 mils)
Topcoat Thickness
37-50 µm (1.5-2 mils)
Maximum Time Between Coats
30 Days
Work together in your teams to address each of the quality-related issues described below. Elect a team spokesperson to present your answers to the class and be prepared to defend them if questioned.
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PCI Study Guide- October 2007
1.
You arrive onto the project site and the contractor has already begun exterior coating application. You measure the prevailing ambient conditions and the surface temperature is within 3°C (5°F) of the dew point temperature, but the surface temperature is higher than the dew point temperature. Based on this scenario, answer the following: Do you allow the contractor to proceed? _________________________________________ If no, why not?
What could have been done to prevent this occurrence?
2.
You measure the thickness of the primer and it is less than the specified minimum by 1 mil. The contractor also measures the thickness of the primer and states that it is within the specified range. How would you resolve this discrepancy?
3.
You were inside the tank obtaining dry film thickness measurements of the primer. Meanwhile, the contractor proceeded with mixing and thinning 10 gallons of the intermediate coat, which you were unable to witness. You inquired as to how much thinner was added to the coating and the mixing crew responded, “We didn’t 52
PCI Study Guide- October 2007 measure, but we estimate probably about a gallon or so…” The product data sheet allows up to 10% thinner addition. Based on this scenario, answer the following: Do you allow the contractor to apply the coating __________________________________ If yes, what do you record on your documentation regarding the amount of thinner added?
If no, what explanation do you provide to the contractor?
4.
The quality control specialist assessed the amount of light inside the tank prior to inspecting the primer for dry film thickness. The amount of light was measured and recorded as 600 Lux (56 foot-candles). Does this conform to the project specification? __________________________________ The same amount of light was available when the contractor applied the primer to the interior surfaces. Is this acceptable? Explain.
5.
The total square footage on the exterior of the tank was estimated to be 1,100 square meters (26,000 square feet). 53
PCI Study Guide- October 2007
6.
5A:
How many 9 square meter (100 square foot) areas must be measured for coating thickness? ____________________________________________________
5B:
What is the minimum number of individual gage readings that must be obtained? ____________________________________________________________________
5C:
How many spot measurements will be obtained? ____________________________
5D:
What is the range of thickness for the spot measurements of the primer? _________
5E:
What is the range of thickness for the spot measurements of the primer + intermediate coats? ___________________________________________________
5F:
What is the range of thickness for the spot measurements of the primer + intermediate + finish coats?______________________________________________
The contractor begins to apply the clear coat to the exterior surfaces and you notice that there is no dissipative dye in the coating as it is being applied. You inquire, and the contractor responds that previous experience with another product resulted in rework because the dye did not fully dissipate, so he refuses to use it. Do you allow the contractor to proceed? ________________________________________ If no, why not?
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PCI Study Guide- October 2007 What could have been done to prevent this occurrence?
7.
Application of the white primer to a portion of the exterior surfaces was done in the early evening around 6:00 PM or so. The next day, you observe a yellowish haze on portions of the surface, which is slightly tacky. As an inspector, what do you suspect occurred? _________________________________ _________________________________________________________________________ Does the presence of this substance put the project at risk? _________________________ _________________________________________________________________________ How would you determine the nature of this substance? ___________________________
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PCI Study Guide- October 2007 Module Five: Coating, Mixing, Thinning and Application: Equipment Overview and Inspection Techniques Quiz 5 1. A product data sheet is considered an __________________for a coating. 2. Calculate a target wet film thickness based on the following data: Dry film thickness: Volume solids content: Thinner addition:
5-7 mils 72% 12.5%
__________________
3. During a material receipt inspection, the inspector should record the following seven items: ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ 4. Most coating manufacturers prohibit mixing of __________________ kits. 5. Most industrial coatings must be mixed using a __________________-type mixing blade. 6. Boxing a coating is not recommended for which two generic types of coatings? __________________ __________________ 7. When inspecting mixing of zinc-rich primers, the __________________component should be slowly sifted into the __________________component while under __________________. 8. Straining of a __________________primer is typically required by the specification or coating manufacturers PDS. 9. Pot agitation is typically required for __________________primers, except moisture-cured __________________zinc-rich primers. 10. What is the first step when considering adding thinner to a coating? _____________________________________ 11. What is the second step when considering adding thinner to a coating? _______________________________ 12. List three consequences of adding an unknown quantity of thinner to a coating. _________________________________________________________________
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PCI Study Guide- October 2007 13. Application of coating to welds, edges, bolt/nuts, and rivets prior to full scale application is known as __________________. 14. __________________ are used to coat crevices and between back-to-back angles. 15. __________________ spray is the most common method used to apply industrial/marine coatings. 16. What is the paint pressure when the regulator on 45:1 airless spray pump is set to 60 psi? __________________ 17. What does the marking 723 indicate on an airless spray tip? __________________ 18. Proper distance of an airless spray gun from the surface is __________________ inches. 19. The upper control on a conventional spray gun controls the __________________. 20. The lower control on a conventional spray gun controls the __________________. 21. Proper distance of a conventional spray gun from the surface is __________________inches. 22. The diameter of the holes in an HVLP spray air cap are __________________ than the holes in a conventional spray air cap. 23. Plural component spray is used to apply coatings with what characteristics? __________________and __________________. 24. For plural component spray, what method is typically used to reduce viscosity of the components? __________________ 25. An applicator should overlap spray passes __________________% to build a consistent thickness. 26. List ten common inspection checkpoints that are performed on nearly every industrial coatings project: ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________ ______________________________
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PCI Study Guide- October 2007 27. What two values are used to determine the relative humidity and dew point temperature when using a sling or battery powered psychrometer in conjunction with the US Weather Bureau Psychrometric Charts? __________________ __________________ 28. Ambient conditions should be measured where __________________. 29. The temperature of the surface to be coated must be at least __________________above the __________________. 30. The wet bulb temperature is considered to be stabilized when two readings taken within __________________seconds are within __________________of one another. 31. A coating material with a six hour pot life and a 45 minute induction has a useable pot life of __________________. 32. The wet film thickness reading on a wet film thickness gage is considered the __________________numbered tooth (step) on the gage. 33. According to SSPC PA2, the accuracy of a coating thickness gage should be verified __________________and __________________ each period of use. 34. A Type 1 gage is known as a __________________gage. 35. A Type 2 gage is known as an __________________ gage. 36. The accuracy of Type 1 gages is verified using __________________. 37. The accuracy of Type 2 gages is verified using __________________. 38. The effect of surface roughness on a coating thickness gage measurement is known as a __________________. 39. The BMR is __________________ from the coating thickness to determine the thickness of the coating above the __________________of the surface profile. 40. If the tolerance of a coating thickness gage is +/- 5% and the tolerance of the standard used to verify gage accuracy is +/- 3%, what is the tolerance of the reading on a 6.4 mil test block? __________________. 41. 41. The BMR is not necessary to measure when a Type 2 gage is verified for accuracy using __________________placed onto the __________________, uncoated steel.
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PCI Study Guide- October 2007 42. How many spot measurements are obtained within an area? __________________ 43. How many individual readings comprise a spot measurement? __________________ 44. The surface to be assessed for DFT represents 600 square feet No. of areas to measure: __________________ Total No. of spots: __________________ Minimum no. of individual gage readings: __________________ 45. The surface to be assessed for DFT represents 24,000 square feet No. of areas to measure: __________________ Total no. of spots: __________________ Minimum no. of individual gage readings: __________________ 46. The surface to be assessed for DFT represents an I-beam that is 40 feet in length, has 12” wide flanges, a 48” web. No. of areas to measure: __________________ Total no. of spots: __________________ Minimum no. of individual gage readings: __________________ 47. According to SSPC PA2, what is the tolerance of a spot measurement for a project specification that specifies 2-4 mils of primer? __________________ 48. When spot or area DFT measurements do conform to the specification requirements, then each __________________ square foot area coated during the same __________________must be inspected. 49. What is the cumulative thickness range of the primer and intermediate coats for a project specification that requires 4-6 mils of primer and 8-10 mils of intermediate coat? __________________ 50. If the coating thickness is 12-15 mils, what Tooke gage tip should be used to make an incision through the coating film to assess layer thicknesses? __________________ 51. The following data was acquired when viewing an incision (made with a 10X cutting tip) through a Tooke Gage lens. What is the thickness of each layer? Primer: 10 divisions: __________________ mils Intermediate: 12 divisions: __________________mils 52. Amine exudate or “blush” can occur on __________________ coatings that are applied and/or cured during __________________conditions.
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PCI Study Guide- October 2007 53. Application of coatings over an amine exudate may result in what type of coating failure? __________________ 54. A pinhole is a __________________in the coating that penetrates to the substrate. 55. A holiday is a __________________ or __________________ in the lining system application. 56. Low voltage, wet sponge pinhole detection is can be used on nonconductive __________________ (up to __________________ mils) applied to a __________________substrate. 57. High voltage, spark testing is can be used on nonconductive __________________ applied to a __________________ substrate. 58. According to NACE RP0188-99, the suggested voltage for testing a coating system that is 41-55 mils thick is __________________. 59. The most reliable method for determining the cure of an ethyl silicate inorganic zinc-rich primer is the __________________test. 60. If a 3H pencil will not scratch or gouge the coating film, but a 4H pencil will, what is the pencil hardness of the coating? __________________ 61. Tensile adhesion testers assess the __________________strength of coatings; while tape adhesion assesses the coatings resistance to __________________. 62. The cross-cut method (Method B) of the tape adhesion test is used for coatings that are less than __________________ mils thick. 63. When a coating breaks cleanly from the substrate, the location of break is __________________. 64. What is the primary difference between conducting an adhesion test per ASTM D3359 (method A) and ASTM D6677? __________________ 65. The gage for measuring the thickness of coatings on concrete (nondestructively) employs an __________________principle of measurement.
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PCI Study Guide- October 2007
Module Five: Coating, Mixing, Thinning and Application: Equipment Overview and Inspection Techniques Supplemental Reading List - Using Coatings Inspection Instruments (SSPC Item #03-08) - Shop Painting of Steel (SSPC Item #02-01) - SSPC Basic Spray Application Manual (SSPC Item #04-05) - Industrial Painter’s Training (SSPC Item #94-09)
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PCI Study Guide- October 2007
Module Six: Industrial and Marine Protective Coatings and Coating Systems Module six introduces the basic components in an industrial coating: non-volatile and volatiles. Subsequently, VOC (volatile organic compound) regulations will be explored in the context of what a QC or QA inspector should know about monitoring and reporting the addition of thinner to coating products and the actual quantity of VOC emitted into the atmosphere during application. In Module Six, participants will also learn how coatings cure. An overview of coating types and coating characteristics will be followed by key inspection concerns by specific coating type. Module Six will conclude with an overview of common coating systems used in a number of industries including: water storage/tanks; power generation (both coal and nuclear); waste water treatment; pulp and paper; lock and dam; chemical plants; buried pipeline; ships/marine vessels and highway/bridges. Learning Outcomes At the completion of this module you should be able to: - Identify basic differences between house paint and industrial/marine protective coatings - List volatile and non-volatile components of a coating - Describe the functions of the resin, additives, pigments, and solvents in a coating - Describe the methods by which coatings cure - Describe the procedures used to identify service environments - List advantages and limitations of various generic types of industrial/marine coatings - Describe functions of the primer, mid-coat and finish coat - Identify common coating systems used by various industries - Describe proper methods used to evaluate coating performance prior to full scale installation Identify Basic Differences Between House Paint and Industrial/Marine Protective Coatings Module Six begins by describing the differences between ordinary household paints and industrial/marine protective coatings. One notable difference is the increased cost of protective coatings, another is the reason behind the higher costs. The performance requirements of industrial/marine coatings are much higher than those of house paints, which are used primarily to improve aesthetics. Protective coatings, on the other hand, may have to withstand immersion in water, chemical exposure, impact and abrasion, as well as provide aesthetics. List Volatile and Non-Volatile Components of a Coating There are many different ingredients or raw materials that are used to formulate an industrial/marine coating. This curriculum divides them into two categories: 1. Volatiles and non-volatiles 2. Pigmentation and vehicle
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PCI Study Guide- October 2007 In the first category, volatiles are part of the wet film, but evaporate into the air once the coating is applied to the surface, while non-volatiles are part of the wet and dry film and remain on the surface once the coating is applied. Describe the Functions of the Resin, Additives, Pigments, and Solvents in a Coating In the second category for coating components, pigmentation and vehicle, the vehicle “carries” the pigmentation to the surface and binds it into the coating film. The vehicle typically consists of the resin or binder, solvents, and any additives that may be included in the formulation. While part of the vehicle evaporates (the solvents) once the coating is applied, other components, like the resin, remain behind as part of the dry film. The resin system cohesively bonds the pigmentation together and adhesively bonds the coating to the underlying substrate or coating layer. In fact, the resin is so significant that the type of resin in the formulation is often used to generically identify the coating. In many cases, the resin system dictates the performance properties of a coating. Additives are also a part of the vehicle that remains on the surface. Additives are added to coating formulations to improve flow-out, surface wetting, and flexibility. Additives can also be used to adjust the consistency of a coating, to resist ultraviolet light, and to prevent settling in the can. In the category of pigmentation and vehicle, the pigment gives the coating the ability to hide the underlying surface. Pigments also give coatings their color and gloss, but pigments may also provide corrosion protection. Pigments like iron oxide or barium can be formulated into a primer to inhibit the corrosion process. Pigments like zinc powder can be added to the primer in sufficient quantities to galvanically protect the underlying carbon steel. Still other pigments, like micaceous iron oxide and leafing aluminum pigments, provide barrier protection. These pigments are plate-like, and the way they position themselves in the coating film forces any moisture that penetrates the coating film to take a longer path to reach the substrate. Extenders are pigments like clay, silica, and mica, which can be incorporated into the formulation to improve film build. Extenders also increase the solids content of a coating and provide added barrier protection. Remember that all pigments, regardless of their individual functions in the coating, remain on the surface and become part of the dry film. When coating components are divided into volatiles and non-volatiles, the solvent system is the volatile component. White it is part of the wet film during application, it is not intended to be part of the dry film once the coating dries or cures. Typically, a blend of solvents is used in the formulation of a coating and each type of solvent in the blend performs a different function. As a general rule, primary solvents reduce the viscosity of the resin, pigments and additives, so the coating can be properly atomized through a spray gun or applied by brush or roller. Primary solvents evaporate from the coating film first, while secondary or coalescing solvents typically remain in the wet film a little longer to help the coating flow-out and knit together to form a uniform, continuous film.
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PCI Study Guide- October 2007 Many solvent systems (and thinners) are categorized as “volatile organic compounds” of VOCs by the U.S. Environmental Protection Agency (EPA). The amount of VOC’s that can be legally emitted into the atmosphere varies from location to location. Some densely populated areas have very strict regulations, while less populated areas typically comply with the Federal limit, which is less restrictive. In the field, the VOC limit is usually dictated by the specification or the local air pollution agency for that project. Fixed facilities like paint shops, however, are sometimes required to log the number of gallons of paint used over a specific period, as well as the VOC content of each type. The local environmental agency regulates the maximum quantity of VOC’s produced by fixed facilities. Coating manufacturers can formulate coatings to comply with VOC regulations by using non-regulated solvents, like water and acetone, or by increasing the non-volatile content of the coating. Since adding thinner in the field may increase VOC levels, the amount of thinner added must be carefully monitored. Describe the Methods by Which Coatings Cure The method in which a coating converts from a liquid to a solid state is known as the curing mechanism. In this module, five basic curing mechanisms are discussed: solvent evaporation, coalescence, oxidation, polymerization and moisture cure. Solvent evaporation is perhaps the most commonly understood coating cure. In this process, the solvent in the coating evaporates into the air after application, while the resin, pigment, and additives remain on the surface to form a dry film. There is no second step or subsequent curing reaction, so the resin can be redissolved by the same solvent system that was used in the blended coating. Coatings that cure by solvent evaporation should not be overcoated with a coating that contains strong solvents. Coalescence also involves evaporation of solvents from the coating film, but in this case there are primary solvents which evaporate first and coalescing solvents (secondary solvents) which remain in the film a little longer (to help fuse the molecules together to form a solid film). After the film has been formed, the secondary solvents also evaporate from the film. This type of cure typically requires a minimum air temperature of 50°F. Oxidation is a third method of coating cure. Components in the coating (drying oils) react with oxygen (from the surrounding air) to form a film. One problem with this method of cure is that the process of oxidation never really stops as long as the coating is exposed to oxygen. Alkyds, which cure by this method, can become very brittle after many years of service, since the resin continues to oxidize long after the coating is fully cured. A fourth method of cure or polymerization is more complex than the first three. Different resin components are carefully measured by the manufacturer and packaged separately, so that when these components are properly blended a chemical reaction occurs, generating a new, resilient coating. The components must be blended in the correct ratios (complete kits) for the chemical reaction (or polymerization) to produce the correct 64
PCI Study Guide- October 2007 blend. Coatings that cure by this method are multi-component, and once they are blended together, the pot life begins. The pot life may vary from a few minutes to several hours. A few of the more common coatings that cure by polymerization are epoxies, aliphatic acrylics, and polyester polyurethanes. Moisture-cure is the fifth method of coating cure discussed. The coating components react with moisture and require a minimum amount of moisture to cure. Moisture-cure urethanes cure this way and release carbon dioxide (CO2) during the process, while inorganic zinc-rich primers also cure by moisture cure, but release ethyl alcohol during the process. The result is a very resilient coating layer, similar to that produced by polymerization. Describe the Procedures Used to Identify Service Environments Properly identifying the service environments is another challenge to the specifier. As the curriculum has pointed out, even when the substrate is prepared according to the specification and the coating is applied properly, the substrate will not be protected if the coating cannot stand up to the service environment. Therefore understanding what the coating system will be subjected to, once applied, is critical. The problem is that service environments aren’t always predictable. For example, when an exhaust stack that was designed to operate at 500°F, undergoes a 1000°F spike, will the coating system fail? There are a number of questions to answer about a service environment before a coating system is selected. Will the coating be subjected to immersion service? If so, will the immersion be constant or intermittent (i.e., splash)? Will the immersion be in potable water, waste water, salt water, solvent, acids, etc.? What is the likelihood and type of physical damage that the coated substrate might sustain (i.e., the impact damage from river debris on a set of dam gates)? Questions on service environments must be answered prior to selecting a coating system. And it should be noted that there may be multiple service environments for a given structure, for example the interior of a chemical plant. Once all the background questions are asked and answered, specifiers can look at the history and performance records of coating systems that have been commonly used in specific industries and service environments. Describe Functions of the Primer, Mid-Coat and Finish Coat Coatings are typically specified in “systems” which consists of the specified surface preparation and the application of one or more coats. Specifiers may recommend multiple layers of the same product, or specify one coating to be used as the primer, another to be used as the midcoat and still another to be used as the topcoat. If the coatings applied are different formulations, they must be compatible with each other. In addition, each layer must be able to perform the function intended for that layer. For example, the function of the primer is to bond the coating system to the substrate. The primer may also be selected to provide corrosion protection to the substrate. The primer 65
PCI Study Guide- October 2007 must be equally compatible with the level of surface preparation beneath it and the coating directly above it. The intermediate coat is typically part of the coating system for the purpose of adding barrier protection. It must also be compatible with the primer and the topcoat. The topcoat is the first line of defense against corrosion and must be resistant to the service environment. Typically, the topcoat must also be aesthetically pleasing (good color and gloss) and be compatible with the underlying coating layer. Identify Common Coating Systems Used by Various Industries Selecting a coating system is based on the prevailing service environment, the intended service life of the structure, the level of surface preparation possible, the intended service life of the coating, access to the structure to be coated, and economical restraints and considerations. Describe Proper Methods Used to Evaluate Coating Performance Prior to Full Scale Installation Another consideration for the specifier when selecting a coating system for an industry is past performance and testing. There are industry specific coating performance evaluations that generate data based on testing that represents the service environment. Once this data is generated, coating manufacturers can access the information and establish their own qualified products lists. The advantage of this type of performance evaluation is that many agencies within a given industry can access performance data with little or no associated costs. An additional method to evaluate the performance of a protective coating or lining system is to employ an industry standard testing procedure designed specifically for a type of coating. The focus of this type of testing is on the performance of the formulated product, not the individual ingredients of the coating. Therefore, the specification/testing includes functions like package stability, application properties, weathering properties, and color and gloss retention. And a final method to evaluate a coating system prior to specifying that system is to employ a combination of the performance evaluations described above. A bridge owner, for example, may refer to industry specific coating performance evaluations, while they simultaneously conduct their own testing for a variety of coating systems on panels of the substrate at the actual site of a future project.
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PCI Study Guide- October 2007 Module Six: Industrial Marine Protective Coatings and Coating Systems Quiz 6 1. The resin, solvent, and additives are known as the ________________ of a coating that carries the _____________________ to the surface and binds it into the film. 2. List five functions of pigmentation in an industrial/marine coating: _____________________________ _______________________________ _____________________________ _______________________________ _____________________________ 3. Solvents are part of the _______ film, but are not part of the ____ film. 4. Primary solvents are used to _______________ __________________; secondary solvents are used to help the coating _____________________. 5. Coatings that “dry” rather than cure form a solid film by a process known as _____________________ ____________________. 6. Waterborne coatings cure by a process known as _________________________. 7. Coatings that cure by a reaction with oxygen cure by ______________________. 8. Multi-component epoxy and polyurethane coating cure by __________________. 9. Coatings that hydrolyze are said to ___________________ cure. 10. What is the primary function of an intermediate coat? _____________________ 11. Which coating system is recommended for use on surfaces with an elevated temperature in a waste water treatment plant? ________________________________________________________________ 12. Mounting test panels containing candidate coating systems in the actual environment where the new coating will be installed is known as a ________________-________________ performance evaluation. 13. Coatings contain two categories of ingredients: _________________ and ____________________________. 14. Thinner addition ______________________ the VOC content of a coating. 15. Prior to selecting a coating system, the facility owner must properly identify the prevailing _______________________ ______________________________. 67
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Module Six: Industrial Marine Protective Coatings and Coating Systems Supplemental Reading List - Protective Coating for Water and Wastewater Facilities (SSPC Item #06-01) - Fundamentals of Chemistry and Composition (SSPC Item #94-17)
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Module Seven: Specialty Inspection Projects Module Seven describes non-routine inspection projects that can pose special challenges to the coatings inspector. Inspecting the surface preparation and coating application in a steel fabrication shop presents a different set of challenges for a coatings inspector, as does maintenance painting in the field when overcoating becomes the maintenance strategy. Additionally, many existing industrial structures contain coatings with toxic metal ingredients. The hazards associated with removal, handling and disposal when these coatings are “disturbed” during maintenance painting operations must be controlled. The inspector may have responsibility for verifying proper set-up and maintenance of containment and ventilation systems, assuring proper worker protection, monitoring air, soil and water quality, and assuring proper handling and disposal of hazardous waste streams. Learning Outcomes At the completion of this module you should be able to: - Describe the unique aspects of performing coatings inspection in a steel fabrication or “blast & paint shop” - Describe the unique aspects of performing coatings inspection on an overcoating project - Describe what the inspector’s role might include on projects involving disturbance of coatings containing toxic metals Describe the Unique Aspects of Performing Coatings Inspection in a Steel Fabrication or “Blast & Paint Shop” Surface preparation and coating application inspection in a steel fabrication shop or a “blast & paint” shop is similar to field inspection. SSPC QP 3 and AISC SPE categorize shops into three types: Covered Shop, Enclosed Shop, Open Shop and Field and both qualification and certification programs require implementation of quality control procedures and documentation. Inspection in the shop includes pre-surface preparation inspection (weld spatter removal; edge preparation; sliver and lamination removal; oil and lubricant removal), surface preparation inspection (abrasive type, size and cleanliness; compressed air cleanliness, surface profile and cleanliness), coating application inspection (ambient conditions monitoring, witnessing mixing and thinning procedures, verifying minimum and maximum recoat intervals, pot life monitoring and application technique; measurement of wet and dry film thickness; assessing intercoat cleanliness and cure; pinhole/holiday detection; and adhesion testing). Describe the Unique Aspects of Performing Coatings Inspection on an Overcoating Project Overcoating is a maintenance strategy that can be employed by a facility owner to reduce costs by extending the life of the existing coating system, verses the cost of totally removing and replacing the coating. There is risk associated with overcoating, so the existing coating system must be carefully evaluated to assess whether it is a candidate for overcoating. The assessment includes tests for substrate condition, amount of corrosion 69
PCI Study Guide- October 2007 and deterioration present, the thickness and adhesion of the existing coating, and the generic type of the existing coating. Test patches can be applied and evaluated prior to full scale overcoating when the condition of the existing coating is marginal. Surface preparation inspection includes verification of oil/grease removal per SSPC-SP 1, and inspection of spot touch-up areas for cleanliness, roughness (if required) and proper feathering of the existing coating for a smooth transition. The remaining surfaces may be brush blasted or pressure washed. These surfaces must be inspected to ensure the existing coating was not severely fractured, and that surface dirt, chalk and other debris has been adequately removed. Testing for chemical contamination may also be required, if soluble salts were deposited onto the surfaces while in service. The inspector may be required to measure and map the thickness of the existing coating, and may be required to measure the wet film thickness of the overcoat material during application. The final dry film thickness can be measured either nondestructively or using a destructive gage. If a nondestructive gage is used, the thickness of the existing system must be deducted from the measurements in order to isolate and document the thickness of the overcoat, or the readings taken in spots where the existing had been totally removed. Adhesion of the overcoat to the existing system may be assessed to ensure that the overcoat is properly bonded, and is similar to the adhesion characteristics of the coating system on a test patch, if one was prepared. Areas where destructive coating thickness and/or adhesion testing were preformed should be touched up by the contractor to prevent premature rusting in these areas. Describe What the Inspector’s Role Might Include on Projects Involving Disturbance of Coatings Containing Toxic Metals The inspector’s role on projects involving removal of coatings containing toxic metals (primarily lead, chromium and hexavalent chromium ) can include inspecting the effectiveness of the containment system by monitoring the air, soils and water around the project site, and by performing visible emissions (VE) monitoring during surface preparation activities. Air quality is monitored by VE observation, or by employing high volume air sampling for total suspended particulate or respirable particulate. Soil and water quality is monitored by collecting and analyzing pre- and post-job samples, or visually. The inspector may also be responsible for verifying that the contractor and his personnel are conforming to their site plan for complying with OSHA’s comprehensive health standard(s) for the toxic metal(s) in the coating, including the implementation of engineering controls, work practices and respiratory protection to control the hazard. The inspector may also evaluate the effectiveness of the ventilation system by measuring air movement inside the containment. Likewise, the inspector should follow the same rules as the contractor’s personnel regarding protective clothing, respiratory protection and use of hygiene facilities on the project site. Finally, the inspector may be responsible for verifying that the contractor is handling and storing all of the waste (hazardous and non-hazardous) properly, and that the waste is tested by an approved laboratory and hauled from the site by a licensed transporter. The inspector may be asked to review the contractor’s site-specific, written worker protection, environmental protection and waste management compliance plans prior to production
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PCI Study Guide- October 2007 work, and may be required to verify conformance to the written plans during production work. Module Seven: Specialty Inspection Projects Quiz 7 1. The primer used on connection points of I beams must often have a Class A or Class B _________________ ___________ if the connection is ________ critical. 2. List four inspection concerns relating to application of primers on slip-critical connections. _____________________________ _________________________________ _____________________________ _________________________________ 3. List three forms of metallized spray: __________________________________ ____________________________ __________________________________ 4. What is the minimum surface cleanliness and surface profile depth for metallizing applied to structures for marine or immersion service? ______________________ 5. Which form of metallizing feeds two wires to a spray gun? __________________ 6. When measuring the thickness of thermal spray coatings on flat surfaces, a minimum of _____ readings are obtained in a line spaced ______ inch apart. 7. When measuring the thickness of thermal spray coatings on a complex geometry, a minimum of _____ readings are obtained in a _______ inch diameter spot. 8. Powder coating may be cured using ______________ or ___________________ 9. List seven inspection check points associated with powder coating application. _____________________________ _________________________________ _____________________________ _________________________________ _____________________________ _________________________________ _____________________________ 10. Application of a liquid coating over a galvanized surface is known as a ___________________ system. 11. __________________ galvanizing is optimum for coating, while _______ galvanizing is difficult to coat. 12. If “sweep blasting” of galvanizing is specified, the inspector may be required to measure the ______________ _______________ __________________ prior to sweep blasting operations.
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13. Most Type 1 and Type 2 DFT gages display the ___________________ thickness of the galvanizing and coating layers. 14. On overcoating projects, the inspector should verify that visible ______________ and ________ contamination are removed prior to _______________ ________________________. 15. Areas of sound coating adjacent to repair areas should be __________________ to ensure a smooth transition for the new coating and to prevent ________________ of the existing coating. 16. If a brush-off blast (SSPC-SP___) is specified for an overcoating project, the inspector may be required to measure __________ _____________ and verify proper abrasive type to ensure neither is too aggressive. 17. Pressure washing to remove dirt, chalking, etc. must be carefully inspected to ensure _________________ removal prior to overcoating. 18. Prior to application of the overcoat material, an inspector should obtain ________________ measurements on the __________________ _____________. 19. The thickness of the overcoat can be isolated from the thickness of the existing coating by using a ________ ___________. 20. List three toxic metals that may be in existing coatings: _________________________________ _____________________________ _________________________________ 21. A containment is designed to protect the ________________________________. 22. Ventilation inside a containment is designed to protect _____________________. 23. SSPC Class __ containment provides the highest level of protection. 24. Negative pressure is monitored _______________ or by reading a _____________________ gage. 25. Air flow inside a containment can be monitored using a ______________ _______ ______________________________. 26. List two devices for monitoring air quality outside of a containment: ___________________________ ____________________________ 27. Pre- and post-project ____________ and/or ______________ sampling and analysis may be required to verify effectiveness of the containment. 72
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28. List three things a coatings inspector should never do inside a regulated area: _________________________________ _____________________________ _________________________________ 29. Hazardous waste can only be transported by ______________ _______________. 30. List two SSPC Guides that govern containment and hazardous waste management procedures: _________________________________ _____________________________
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Module Eight: Coating Failures: Investigation Procedures and Case Studies Module Eight explains how knowledgeable coatings inspectors can help avoid coating failure. The role of the coatings inspector and the types of inspection activities that can play a role in preventing the failures are described. Case histories of actual coating failures are presented. The cause, fault and repair procedures are explored, and avoidance methods are discussed. Learning Outcomes At the completion of this module you should be able to: - Describe how coatings inspection can help prevent premature coating failures Describe How Coatings Inspection Can Help Prevent Premature Coating Failures Coatings can fail for a variety of reasons. When a coating failure occurs, an investigation is often performed to determine the cause, determine the part responsible and assess the degree of repair necessary to ensure the integrity of the substrate. The consequences of coating failure can include substrate repair or replacement, costly rework and down time, and aesthetics. When investigating a coating failure, six issues should be considered, including what was to be done; does it make sense; what was actually done; what caused the failure to occur; who is the responsible party; and what can be done now. A coating failure investigation includes both a site investigation and a laboratory investigation. The site investigation includes document acquisition, a determination of the construction sequence and obtaining the structure and painting history, visual observations, sample and data collection, acquisition of batch retains and other coating samples, and photography. The laboratory investigation can include a variety of forensic tests, depending upon the nature of the coating failure. Coating inspection aids in coating failure avoidance by detecting problems and nonconformities (and verifying they are corrected) prior to putting the coating or lining into service. Coatings inspection however cannot aid in failure avoidance when a coating is improperly formulated or when a faulty specification is generated and work is completed based on a faulty contract. The role of the coating inspector can be critical in a failure investigation. Well-prepared, thorough records and photographic documentation can greatly help to narrow the cause of the failure.
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Module Eight: Coating Failures: Investigation Procedures and Case Studies Quiz 8 1. List six possible causes of premature coating failure: ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ ________________________________ 2. List four consequences of coating failures: _______________________________ ________________________________ ________________________________ ________________________________ 3. Describe how a coatings inspector can help prevent coating failures from occurring. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 4. What key item maintained by an inspector is critical to a coating failure investigation? _____________________________________________________________________
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Module Eight: Coating Failures: Investigation Procedures and Case Studies Supplemental Reading List - Failure Analysis of Paints and Coating (SSPC Item #04-14) - Visual Comparison Manual: Application and Coating Defects (SSPC Item #99-01) - Paint Film Degradation (SSPC Item #01-14)
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Module Nine: Inspector Safety Module Nine describes basic inspector safety. Fabrication shops and construction sites often pose significant safety concerns for a coatings inspector. While Module Nine is not designed to provide comprehensive safety training, it makes the coatings inspector aware of potential hazards and methods of prevention. Safety issues described in Module Nine include fall prevention/protection, respiratory protection, sight and hearing protection, protection from toxic metals, and confined space entry hazards. Module Nine also describes the purpose of site specific environmental, safety and health hazards planning and the inspector’s responsibility for personal safety. Learning Outcomes At the completion of this module you should be able to: - List potential safety hazards associated with coatings inspection - Describe the common personal protective equipment used by a coatings inspector List Potential Safety Hazards Associated with Coatings Inspection Coatings inspection are frequently classified as “workers” and held by law to be responsible, as far as is reasonable, for their own safety. Everyone at the jobsite should keep a look-out for unsafe acts or operations. An inspector who is aware of a serious safety violation but fails to report it to the effected workers’ supervisor may put themselves at risk of legal action if an accident occurs. The coatings inspector can face general risks, personal risks, and legal risks. The inspector is responsible to know what the risks are, and to take reasonable steps to avoid them. The coatings inspector can encounter hazardous materials, hazardous environments and hazardous activities on a project. Hazardous materials include cleaning solvents, abrasives and dusts, toxic metals, coating components, thinners, chemical strippers and acidic and caustic solutions. Hazardous environments include heights, confined spaces, electrical, fire and explosion hazards, slippery or obstructed walkways, excessive heat, inadequate lighting, noise, vehicles and moving heavy parts on cranes, etc. Hazardous activities include solvent cleaning, abrasive blast cleaning, high pressure waterjetting, power tool cleaning and airless spraying. Material Safety Data Sheets (MSDS) are mandated under OSHA’s Hazard Communication (Hazcom) regulation and are the primary document that describes the hazards associated with the chemicals used on a project and the personal protective equipment required to safely handle the product. Describe the Common Personal Protective Equipment Used by a Coatings Inspector While the inspector receives a shorter duration of exposure to hazards than workers, the hazards themselves are similar and coatings inspector should wear similar, suitable safety equipment and clothing. Personal protective equipment for an inspector typically includes a hard hat and safety glasses, ear plugs in a noisy environment, respiratory
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PCI Study Guide- October 2007 protection, a fall harness and shock absorbing lanyard (if working form heights greater than 1.8 meters [six feet]), work boots and long sleeved coveralls. Most battery-operated inspection equipment is not “intrinsically safe” and should not be used in a hazardous environment (greater than 10% of the LEL) without the appropriate permit.
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Module Nine: Safety Quiz 9 1. The coatings inspector shares in the responsibility for the safety of ______________ and the _______________. 2. A coatings inspector that observes an imminent hazard that may cause death or serious injury should take _______________________ action to prevent the _____________________. 3. Who should an inspector obtain guidance from regarding their role relative to safety issues? ___________________________________________________ 4. List an example of a “General Risk” that a coatings inspector may be exposed to: _______________________________________ 5. List an example of a “Personal Risk” that a coatings inspector may be exposed to: _______________________________________ 6. What is the primary difference between exposure hazards associated with inspection verses exposure hazards to painters? __________________________ ________________________________________________________________ 7. List two “hazardous materials” that will be present on every coatings project: ___________________________ _________________________________ 8. The inside of a storage tank can be considered what type of “hazardous environment?” _______________________________ 9. Why is airless spraying categorized as a “hazardous activity?” ______________________________________________________________ 10. The effect of hazardous materials on an inspector’s health depends on the ________________, __________________ and route of ________________. 11. List four items that are of the greatest value to an inspector on an MSDS: __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ __________________________________________________________________ 12. What is the most frequent way solvents affect the body? ____________________
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PCI Study Guide- October 2007 13. Polyurethane coatings contain a chemical known as _______________________, which are strong irritants and ________________________. 14. Respirators equipped with ___________ filtration cartridges can filter _____________________ sized-dust. 15. Heights greater than _____________ above a lower level require fall protection. 16. What type of lanyard is a component to a personal fall arrest system? ________________________________ 17. List three items that an inspector should verify before entering a confined space: ________________________________ ____________________________ ________________________________ 18. What electrical hazard cannot typically be locked-out/tagged-out? ________________________________________________________________ 19. What hazard is associated with inadequate lighting? ______________________ 20. List two basic types of respirators: _______________ & ___________________ 21. Most coating inspection gages are not ___________________ safe and should not be used in _______________________ environments.
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Module Nine: Safety Supplemental Reading List - Industrial Lead Paint Removal Handbook (SSPC Item #93-02) - Fall Protection for Construction (SSPC Item #132-K) - Scaffolding Training Program (SSPC Item #106-K) - Guides on Environmental Protection (SSPC Item #05-01)
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Module Ten: Navigating Coating Specifications Module Ten explains the purpose and content of coatings specifications. The coatings specification is the inspector’s “rule book” for a coatings project. It describes the scope of work and the requirements of the contract, as well as lists the inspection checkpoints for which the inspector is responsible. The importance of a properly prepared coatings specification and the general layout and components in a specification are described in Module Ten. Learning Outcomes At the completion of this module you should be able to: - Describe the purpose and function of a coating specification - List the various methods in which coatings are specified for use - List the basic components of a coating specification - Locate inspection check points in a coatings specification Describe the Purpose and Function of a Coating Specification A properly prepared specification is a key component to project success. A coatings specification describes the project and the objective of the coating system. It also describes the materials required to complete the work, the intended appearance of the completed work and lists the inspection hold points/check points to help assure that the work is done according to the requirements of the specification. A coating specification is a legally binding document. It is a contract between the owner and the contractor. While a coatings specification is a legal document, it must be workable and understandable. A coating specification should also be practical, so that the owner can effectively communicate the desired outcome, including the project schedule. The specification should not be unreasonably restrictive, but should anticipate problem areas that the contractor may encounter and must overcome to successfully complete the contract. There are two general types of specification for coating work: those involved with new construction and those involved with maintenance painting of existing structures. The content of the specification documents will be different in both cases. List the Various Methods in Which Coatings are Specified for Use There are a number of ways that coating systems can be specified for use on a project. Some specifications are written around specific product trade names, and some are written as “trade name or equal.” Others are based on a pre-established “Qualified Products Lists” (QPL), or are based on a set of performance standards. While infrequent, a coating system can also be specified based on a coating formulation or set of formulations. List the Basic Components of a Coating Specification 82
PCI Study Guide- October 2007 Most coating specifications contain three basic components: General; Products (materials); and Execution. Module Ten: Navigating Coating Specifications Quiz 10 1. A coating specification is an inspector’s __________ ____________ for a coatings project. 2. An inspector should read and understand the coating specification ____________ the project begins. 3. List two types of specifications for coating work: ____________________________ ________________________________ 4. What should an inspector do when the specification is poorly-prepared or does not contain specific requirements? _________________________________________ __________________________________________________________________ 5. What likely becomes the governing document when there is no specification for a coatings project? __________________________________________________ 6. List three basic parts to a coating specification: _____________________ ________________________________ _____________________________ 7. In which of the three Parts of a coatings specification listed in Question 6 are the references and definitions found? _____________________________________ 8. In which of the three Parts of a coatings specification listed in Question 6 are the coatings listed that will be used on a project? ____________________________ 9. In which of the three Parts of a coatings specification listed in Question 6 is the degree of surface cleanliness identified? ____________________________ 10. In which of the three Parts of a coatings specification listed in Question 6 is the thickness range of each coat listed? _________________________________
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Module Eleven: Specification Review and Pre-Construction Conference; Inspection Plan Development for the Inspection of Fuel Tank Lining Installation Module Eleven describes the purpose and content of a pre-construction conference and explains how to prepare an inspection plan. After a careful review of the project specification during the Module Ten workshop, a preconstruction conference will be conducted. Participants are provided with an agenda of discussion items, photographs of the project site and Product Data Sheets and MSDSs for the coatings selected for the project. The course instructors represent the painting contractor and the coating manufacturer. The participants are divided into two groups; one group role play the Quality Assurance Inspector representing the facility owner, while the other group role plays the contractor’s Quality Control Inspector. **It should be noted that this module is completed in a team setting, which is considered key to completing the practical exam with success. Opting out of the classroom portion of the course does not permit access to this workshop.** Learning Outcomes At the completion of this module you should be able to: - Completion of Module Eleven will enable the coatings inspector to participate in pre-construction conferences and prepare an inspection plan/procedure.
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Module Twelve: Simulated QA/QC Inspection of Fuel Tank Interior Lining Installation Module Twelve includes an inspection workshop which enables the participants to apply learned skills from the previous eleven modules. Ten inspection stations are equipped with instruments, visual guides and miscellaneous equipment and test plates. Participants work in small groups to perform inspections at each station, document the results of the inspections and compare the results to the project specification provided in Module Ten and the inspection procedures developed in Module Eleven. After all the groups have completed all of the stations, the participants reconvene and discuss any problems and non-conformities observed. **It should be noted that this module is completed in a team setting, which is considered key to completing the practical exam with success. Opting out of the classroom portion of the course does not permit access to this workshop.** Learning Outcomes At the completion of this module you should be able to: - Completion of Module Twelve will enable the coatings inspector to perform coatings inspection, document inspection data, and compare inspection results to specification requirements.
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PCI Study Guide- October 2007 Appendix A Quiz Answer Keys
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PCI Study Guide- October 2007 Appendix A Quiz Answer Keys
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PCI Study Guide- October 2007 Appendix A Quiz Answer Keys
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SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 1 QUIZ ANSWER KEY
1. Corrosion is defined as the deterioration of metallic surfaces 2. Carbon steel releases energy during the corrosion process. 3. The use of protective coatings is the most widely used method of corrosion control. 4. List four elements of a corrosion cell: Anode Metallic Pathway
Cathode Electrolyte
5. Which of the four elements in question 4 does a protective coating prevent from contacting the steel? Electrolyte 6. When corrosion occurs, the anode depletes or decays. 7. If a copper pipe is connected to an aluminum pipe without an insulator, which metal represents the anode? Aluminum 8. List two dissimilar metals that are intentional coupled in the protective coatings industry as a method of corrosion prevention? zinc and aluminum 9. What type of chemical will deteriorate uncoated weathering steel? Salt 10. Lamellar pigments form plate-like layers and provide barrier protection to steel surfaces. 11. What two elements are prevented from contacting the steel when a barrier-type coating is employed? Water (electrolyte) and air (oxygen). 12. Zinc-rich primers protect the steel by barrier and sacrificial protection. 13. Thermal spray metallizing and galvanizing protect the steel by barrier and sacrificial protection. 14. Borates, chromates, phosphates and other pigments protect the steel by inhibition. 15. Cathodic protection can be in the form of sacrificial anode or impressed current. 16. Sacrificial anode is considered passive cathodic protection. A-2
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17. Impressed current is considered active cathodic protection. 18. Cathodic protection is used in conjunction with protective coatings. 19. Aluminum and copper are metals that form a protective oxidation layer. 20. When corrosion occurs, the steel is releasing (giving up) energy.
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SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 2 QUIZ ANSWER KEY
1. Quality Control is performing observations and tests, and documenting that the work meets/exceeds the specification requirements. 2. Quality Control is the contractor’s responsibility. 3. Quality Assurance is the process to verify the quality of work performed as reported by quality control personnel. 4. Quality Assurance is performed by the owner or a third party on behalf of the owner. 5. When an _owner performs QA with his direct staff, he has a contractual relationship with the contractor and can exert control. 6. When a third party performs QA for the owner, he does not have a contractual relationship with the contractor and can only advise and document, and advise the contractor’s QC. 7. Independent of whether Quality Assurance personnel are on-site, the contractor remains responsible for quality control. 8. When work is halted for an inspection, it is known as a hold point inspection. 9. List six common hold point inspections: Pre-cleaning Intermediate Coat Application Surface Preparation Topcoat Application Primer Application Cure 10. Which party should inspect the completed work first, QA or QC? QC 11. If the inspected area is deficient, which party should inspect the surface first after the rework is completed, QA or QC? QC 12. QA observations and test results typically supersede those of QC. 13. Prior to a pre-construction conference an inspector should review the specification
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PCI Study Guide- October 2007 14. List seven topics that should be discussed at a pre-construction conference: Contractor’s Proposed Operation Lighting Inspector Safety and Access Product Information Inspection & Measurement Visual Standard Inaccessible Areas 15. An inspection plan can contain three columns, titled as: Inspection Chechpoint Inspection Method Acceptance Criteria 16. The content of the “acceptance criteria” section for an inspection plan comes from the specification. 17. A Work Plan should cover the individual phases of a project, including both production and inspection. 18. A Work Plan is also known as a Process Control Plan. 19. One of the most important responsibilities of a coatings inspector is to document the results of inspections. 20. Fraudulent documentation, falsification of time/expense reports and acceptance of gifts in exchange for lenient inspection are ethical breaches.
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PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 3 QUIZ ANSWER KEY
1. Preparing a surface for coating application is the most critical and typically the most costly step. 2. List five common responsibilities of a coatings inspector relating to surface preparation: Abrasive Cleanliness Compressed Air Cleanliness Removal of Grease/Oil Contamination
Surface Cleanliness Surface Profile (roughness)
3. The two-fold purpose of surface preparation is to clean and roughen the substrate. 4. ASTM International and NACE International have prepared a standard and a recommended practice for measurement of surface profile. 5. The specification dictates the required surface profile depth. 6. The surface profile or anchor pattern must be compatible with the entire coating system. 7. List two “fabrication defects” that may be addressed in a coating specification. Weld Spatter Edges/Corners Laminations/Slivers 8. List three methods that can be used to inspect surfaces for the presence of grease/oil: Visual (rag) Black Light Water Break Test 9. Pack Rust occurs between mating surfaces, while stratified rust forms on the surface of the steel. 10. Chemical contaminants like chloride trapped beneath a coating film can cause osmotic blistering, underfilm corrosion and premature failure. 11. Testing for chemical contamination involves two steps: Extraction and Analysis. 12. Immersion environments are more conducive to coating deterioration caused by chemical contamination beneath the coating film than atmospheric environments. 13. Suggested thresholds for soluble salt concentrations are found in the appendix to SSPC SP12/NACE No. 5, “High and Ultra-High Pressure Water Jeting” A-6
PCI Study Guide- October 2007 14. The depth and shape of the surface profile generated by abrasive blast cleaning is determined by the type and size of abrasive and the hardness of the surface. 15. Abrasives fall into two general categories, Expendable and Recyclable. 16. SSPC AB 1 categorizes abrasives according to Type, Class and Grade. 17. The abrasive cleanliness requirements in SSPC abrasive specifications AB1, AB2 and AB3 are indirect requirements of the SSPC abrasive blast cleaning surface cleanliness standards. 18. List four tests that an inspector can perform in the field to verify conformance to SSPC AB1: Water soluble contaminants Surface Profile Yield Oil Content Particle Size Distribution (sieve analysis) 19. SSPC AB2 governs the quality of recycled ferrous metallic abrasives. 20. Steel grit produces an angular-shaped surface profile. 21. Steel shot produces a round-shaped surface profile. 22. List three tests that an inspector can perform in the field to verify conformance to SSPC AB3: Size Cleanliness Conductivity 23. List one test that an inspector cannot perform in the field to verify conformance to SSPC AB2: Lead Content 24. The diameter of an S330 steel shot abrasive is 0.330mm. 25. Which abrasive is larger, G25 or G50? G25. 26. Centrifugal blast machines often incorporate a blend of steel shot and steel grit abrasives. 27. Wet abrasive blast cleaning is used when airborne dust must be controlled. 28. High pressure water jetting incorporates pressures from 35 to 69 MPa. 29. Chemical strippers do not remove rust or mill scale and will not generate a surface profile. 30. Three methods used to prepare concrete for coating include: Mechanical methods Chemical methods Thermal methods
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PCI Study Guide- October 2007 31. SSPC surface cleanliness standards become contract law once they are invoked by the specification. 32. SSPC-SP1, “Solvent Cleaning” is an indirect requirement of the SSPC surface cleanliness standards. 33. SSPC-SP2 “Hand Tool Cleaning” requires the removal of all loosely adhering rust, mill scale & paint. 34. SSPC-SP2 requires the use of a dull putty knife as the inspection tool. 35. SSPC-SP3 “Power Tool Cleaning” requires the removal of all loosely adhering mill scale, rust & paint. 36. What is the primary difference between SSPC-SP15, “Commecial Grade Power Tool Cleaning” and SSPC-SP11, “Power Tool Cleaning to Bare Metal?” SSPC-SP15 allows up to 33% staining to remain in each 9 square inches of surface, where SSPC-SP11 does not permit any staining. 37. In addition to solvent cleaning compressed air cleanliness is an indirect requirement of SSPC-SP3, SP15 and SP11. 38. Which two SSPC surface cleanliness standards invoke a minimum surface profile requirement? SSPC-SP11 and SSPC-SP15 What is the minimum requirement? Minimum of 1 mil (25 microns) 39. List three possible “indirect requirements” of the SSPC abrasive blast cleaning s tandards: Solvent cleaning (SSPC-SP1) Abrasive cleanliness Compressed air cleanliness (ASTM D4285) 40. The amount of staining allowed by the SSPC abrasive blast cleaning standards is based on what area? 9 square inches (58 cm2) 41. SSPC-SP7/NACE No. 4, “Brush-off Blast Cleaning” requires the removal of all loosely adhesring rust, paint & mill scale. 42. SSPC-SP14/NACE No. 8, “Industrial Blast Cleaning” allows up to 10% intact rust, paint or mill scale to remain. The amount of staining is unlimited. 43. The only difference between SSPC-SP 6/NACE No. 3, “Commercial Blast Cleaning” and SSPC-SP10/NACE No. 10, “Near-White Blast Cleaning” is the percentage of allowable staining. SP6 allows up to 33% staining, where SP10 allows up to 5% staining (of each 9 square inches of surface).
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PCI Study Guide- October 2007 44. SSPC-SP6/NACE No. 3 allows up to 33% staining to remain on each 9 square inch area. 45. SSPC-SP10/NACE No. 2 allows up to 5% staining to remain on each 9 square inch area. 46. SSPC-SP5/NACE No. 1 allows no paint, rust, mill scale or straining to remain. 47. SSPC-SP12/NACE No. 5, level WJ-2 allows up to 5% of the surface to contain straining or tightly adhering matter. 48. The “L” in “SSPC SP12-WJ-3-L” indicates light flash rusting is permitted by the specification. 49. ISO St2, “Thorough Hand and Power Tool Cleaning” requires removal of all poorly adhering materials. 50. ISO Sa 2 1/2, “Very Thorough Blast Cleaning” allows only stains to remain on the surface. 51. The SSPC/NACE and ISO cleanliness standards prohibit the use of magnification when inspecting surface cleanliness. 52. Prior to final surface preparation, it is recommended that the inspector verify that the surface temperature is at least 5oF (3oC) higher than the dew point temperature. 53. Dehumidification equipment removes moisture from the air. 54. List three methods of dehumidification: Compression; Refrigeration; Dessication 55. Cooling air below the dew point for dehumidification of the air is the Refrigeration method. 56. Products that absorb moisture from the air as a means of dehumidification use the Dessication method. 57. Indicate the procedure for conducting a compressed air cleanliness test, below: Conduct the test down stream of moisture and oil separation. Position the air outlet 18” from the collector Exhaust the compressed air onto the collector for approximately one minute. 58. To conduct a “vial test,” fill a clear container with 1/3 abrasive and an equal amount of clean tap water. Allow the shaken blend to settle for 30 minutes.
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PCI Study Guide- October 2007 59. The maximum abrasive conductivity according to the SSPC abrasive specifications is 1000 µS. 60. The minimum level of lighting for inspection is 538 Lux. 61. The recommended level of lighting for inspection is 200 ft/candles. 62. The visual standard reference “G2 SP14” in SSPC VIS 1 indicates: Weathered coating system over mill scale with moderate pitting abrasive blast cleaned to an “Industrial Blast” level 63. The visual standard reference “F SP3 PWB” in SSPC VIS 3 indicates: Previously painted steel surface; mostly intact zinc-rick primer applied to a blast cleaned surface, power tool cleaned using a power wire brush 64. The visual standard reference “D WJ3 M” in SSPC VIS 4/NACE VIS 7 indicates: Rusted and pitted steel surface prepared by “thorough” water jetting; with moderate rust back permitted 65. The visual standard reference “C WAB 6 H” in SSPC VIS 5/NACE VIS 9 indicates: Rusted steel surface prepared by wet abrasive blast cleaning to a “Commercial Blast” level; with heavy rust back permitted 66. The visual standard reference “A Sa3” in ISO 8501-1:1988 indicates: Steel surface containing adhering mill scale, blast cleaning to a “visually clean”level 67. Surface profile is defined as the maximum peak-to-valley depth. 68. Profile generation increases the surface area of the steel. 69. An increase in peak count reportedly enhances coating adhesion and a greater resistance to corrosion undercutting. 70. The G/S comparator disc is selected for inspection of surface profile when garnet abrasive is used to perform abrasive blast cleaning. 71. “3.0SH76” on a comparator disc segment indicates: 3 mil surface profile; Shot comparator disc; 1976. 72. Verify “zero-set” on a surface profile depth micrometer using a glass plate. 73. The measuring range of X-Coarse replica tape is 1.5-4.5 mils. 74. The thickness of the Mylar film on replica tape is 2 mils. 75. Each grade of replica tape is most accurate in the middle of the range.
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PCI Study Guide- October 2007 76. Complete the following chart: Parts Per Million Chloride Amount of Extraction Liquid Micrograms of Chloride Area Extracted Micrograms per cm2 chloride
176 2 mL 352 µg 12.25 cm2 28.7 µg/ cm2
77. Complete the following chart: Conductivity of sample Conductivity of blank Net Conductivity of sample
120 µS/cm 8.7 µS/cm 111.3 µS/cm
78. Convert 35 µS/cm to surface chloride concentration using the formula on Page 3-147. E = 0.3 x S x (V/A) 0.3 x 35 x (2÷12.25)= 1.71µg/cm2 79. A pH of 10 is considered alkaline 80. A pH of 3 is considered acidic
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PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 4 QUIZ ANSWER KEY 1. Average the following set of surface profile measurements: 3.5, 3.7, 2.9, 3.1, 4.0 3.4 mils 2. Convert 39% to decimal format.
0.39
3. Calculate the amount of thinner to add to 10 gallons of mixed coating to be reduced 20%. 2 gallons 4. Calculate the area of a square that is 4.5 feet x 13.6 feet. 61.2 square feet 5. Calculate the area of an I-beam that is 40 feet in length, has 12” wide flanges, a 48” web, and 8 stiffeners (4” wide x 48” long). 491 square feet 6. Calculate the exterior surface area of a tank that is 45 feet in height and 90 feet in diameter. C = 3.14 x 90 feet = 283 feet Area of roof (A) = 90 ÷ 2 = 45; 3.14 x 452 = 6359 sq. ft. 45 x 283 = 12,735 sq. ft. 12,735 + 6359 = 19,094 sq. ft. Calculate the volume of water the tank in Question 6 will hold. (3.14 x 452) x 45 = 286,133 cubic feet 286,133 cu. Ft. x 7.48 gallons/cu. Ft. = 2,140,275 gallons 7. Convert 2.4 pounds/gallon VOC to grams/Liter. 288 g/L 8. Convert 64oF to oC. 18oC 9. Convert 275 micrometers to mils 11 mils 10. Calculate the quantity of primer required to coat 15,000 square feet of blast cleaned steel, based on the following data: Specified Dry Film Thickness: 3-5 mils Volume Solids Content: 84% Mixing/Application Loss Estimate: 25% Surface Roughness Loss Estimate: 20% Recommended Thinner Addition: One pint per gallon 1604 ÷ 5 mils = 321 sq. ft./gal. 321 x 0.84 = 270 sq. ft./gal. 270 x 0.75 = 203 sq. ft./gal. 203 x 0.80 = 163 sq. ft./gal. 15,000 sq. ft. ÷ 163 sq. ft./gal. = 92 gallons A-12
PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 5 QUIZ ANSWER KEY 1. A product data sheet is considered an instruction manual for a coating. 2. Calculate a target wet film thickness based on the following data: Dry film thickness: Volume solids content: Thinner addition:
5-7 mils 72% 12.5%
8-11 mils WFT
3. During a material receipt inspection, the inspector should record the following seven items: Name of Coating Manufacturer Thinner Manufacturer Product Name Thinner Name/No. Product No. batch No. of Thinner Batch No. of Each Component 4. Most coating manufacturers prohibit mixing of partial kits. 5. Most industrial coatings must be mixed using a shear-type mixing blade. 6. Boxing a coating is not recommended for which two generic types of coatings? Inorganic zinc-rich primers Moisture-cure Urethanes 7. When inspecting mixing of zinc-rich primers, the zinc powder component should be slowly sifted into the liquid component while under agitation. 8. Straining of a zinc-rich primer is typically required by the specification or coating manufacturers PDS. 9. Pot agitation is typically required for zinc-rich primers, except moisture-cured single component zinc-rich primers. 10. What is the first step when considering adding thinner to a coating? Determine whether thinning is permitted by the manufacturer and specification 11. What is the second step when considering adding thinner to a coating? Determine the type and amount of thinner to be added 12. List three consequences of adding an unknown quantity of thinner to a coating. Net effect on VOC content is unknown Target WFT is unknown May result in sagging and/or accelerated surface drying A-13
PCI Study Guide- October 2007
13. Application of coating to welds, edges, bolt/nuts, and rivets prior to full scale application is known as stripe coating. 14. Daubers are used to coat crevices and between back-to-back angles. 15. Airless spray is the most common method used to apply industrial/marine coatings. 16. What is the paint pressure when the regulator on 45:1 airless spray pump is set to 60 psi? 2,700 psi 17. What does the marking 723 indicate on an airless spray tip? 14” fan when gun is positioned 12” from the surface; 0.023” tip opening 18. Proper distance of an airless spray gun from the surface is 12 inches. 19. The upper control on a conventional spray gun controls the shape of the fan pattern. 20. The lower control on a conventional spray gun controls the amount of paint that exits the spray tip. 21. Proper distance of a conventional spray gun from the surface is 6-8 inches. 22. The diameter of the holes in an HVLP spray air cap are larger than the holes in a conventional spray air cap. 23. Plural component spray is used to apply coatings with what characteristics? Short Pot Life and 100% Solids 24. For plural component spray, what method is typically used to reduce viscosity of the components? Heated material hoses 25. An applicator should overlap spray passes 50% to build a consistent thickness. 26. List ten common inspection checkpoints that are performed on nearly every industrial coatings project: Verification of correct materials Verification of correct materials Verification of current shelf life Verification of correct materials Measuring ambient conditions & surface temp. Mixing procedures Measuring coating temperature Assessing intercoat cleanliness Measuring DFT Verification of rcoat times/temperatures
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PCI Study Guide- October 2007
27. What two values are used to determine the relative humidity and dew point temperature when using a sling or battery powered psychrometer in conjunction with the US Weather Bureau Psychrometric Charts? Air Temperature Depression of wet bulb thermometer (from dry bulb) 28. Ambient conditions should be measured where the work will be performed 29. The temperature of the surface to be coated must be at least 5oF (3oC) above the Dew Point Temperature. 30. The wet bulb temperature is considered to be stabilized when two readings taken within 20-30 seconds are within 0.5o of one another. 31. A coating material with a six hour pot life and a 45 minute induction has a useable pot life of 5 hours & 15 minutes. 32. The wet film thickness reading on a wet film thickness gage is considered the highest (wetted) numbered tooth (step) on the gage. 33. According to SSPC PA2, the accuracy of a coating thickness gage should be verified before and after each period of use. 34. A Type 1 gage is known as a magnetic pull-off gage. 35. A Type 2 gage is known as an electronic gage. 36. The accuracy of Type 1 gages is verified using calibration blocks. 37. The accuracy of Type 2 gages is verified using non-metallic foils or plastic shims. 38. The effect of surface roughness on a coating thickness gage measurement is known as a base metal reading. 39. The BMR is subtracted from the coating thickness to determine the thickness of the coating above the peaks of the surface profile. 40. If the tolerance of a coating thickness gage is +/- 5% and the tolerance of the standard used to verify gage accuracy is +/- 3%, what is the tolerance of the reading on a 6.4 mil test block? 6-6.8 mils (+/- 6%, which is +/-0.4 mil) 41 The BMR is not necessary to measure when a Type 2 gage is verified for accuracy using plastic shims placed onto the prepared, uncoated steel. 42. How many spot measurements are obtained within an area? 5
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PCI Study Guide- October 2007 43. How many individual readings comprise a spot measurement? Minimum of 3 44. The surface to be assessed for DFT represents 600 square feet No. of areas to measure: 3 Total No. of spots: 15 Minimum no. of individual gage readings: 45 45. The surface to be assessed for DFT represents 24,000 square feet No. of areas to measure: 26 Total no. of spots: 130 Minimum no. of individual gage readings: 390 46. The surface to be assessed for DFT represents an I-beam that is 40 feet in length, has 12” wide flanges, a 48” web. No. of areas to measure: 5 Total no. of spots: 70 Minimum no. of individual gage readings: 210 47. According to SSPC PA2, what is the tolerance of a spot measurement for a project specification that specifies 2-4 mils of primer? 1.6 – 4.8 mils 48. When spot or area DFT measurements do conform to the specification requirements, then each 100 square foot area coated during the same work shift must be inspected. 49. What is the cumulative thickness range of the primer and intermediate coats for a project specification that requires 4-6 mils of primer and 8-10 mils of intermediate coat? 12-16 mils 50. If the coating thickness is 12-15 mils, what Tooke gage tip should be used to make an incision through the coating film to assess layer thicknesses? 2X 51. The following data was acquired when viewing an incision (made with a 10X cutting tip) through a Tooke Gage lens. What is the thickness of each layer? Primer: 10 divisions: 1 mils Intermediate: 12 divisions: 1.2 mils Topcoat: 20 divisions: 2 mils 52. Amine exudate or “blush” can occur on epoxy coatings that are applied and/or cured during high humidity, cool conditions. 53. Application of coatings over an amine exudate may result in what type of coating failure? Intercoat delamination 54. A pinhole is a tiny void in the coating that penetrates to the substrate.
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PCI Study Guide- October 2007
55. A holiday is a skip or miss in the lining system application. 56. Low voltage, wet sponge pinhole detection is can be used on nonconductive coatings (up to 20 mils) applied to a conductive substrate. 57. High voltage, spark testing is can be used on nonconductive coatings applied to a conductive substrate. 58. According to NACE RP0188-99, the suggested voltage for testing a coating system that is 41-55 mils thick is 4000 volts. 59. The most reliable method for determining the cure of an ethyl silicate inorganic zinc-rich primer is the solvent rub test. 60. If a 3H pencil will not scratch or gouge the coating film, but a 4H pencil will, what is the pencil hardness of the coating? 3H 61. Tensile adhesion testers assess the pull-off strength of coatings; while tape adhesion assesses the coatings resistance to peel-back. 62. The cross-cut method (Method B) of the tape adhesion test is used for coatings that are less than 5 mils thick. 63. When a coating breaks cleanly from the substrate, the location of break is adhesion. 64. What is the primary difference between conducting an adhesion test per ASTM D3359 (method A) and ASTM D6677? Tape is not used on the X-cut when conducting testing per ASTM D6677 65. The gage for measuring the thickness of coatings on concrete (nondestructively) employs an ultrasonic (ultrasound) principle of measurement.
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PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 6 QUIZ ANSWER KEY
1. The resin, solvent and additives are known as the vehicle of a coating that carries the pigment to the surface and binds it into the film. 2. List five functions of pigment in an industrial/marine coating: Color Barrier protection Hiding power Corrosion (inhibitive) protection Gloss level of coating 3. Solvents are part of the wet film, but are not part of the dry film. 4. Primary solvents are used to reduce viscosity; secondary solvents are used to help the coating flow and knit together. 5. Coatings that “dry” rather than cure form a solid film by a process known as solvent evaporation. 6. Waterborne coatings cure by a process known as coalescence. 7. Coatings that cure by a reaction with oxygen cure by oxidation. 8. Multi-component epoxy and polyurethane coating cure by polymerization. 9. Coatings that hydrolyze are said to moisture cure. 10. What is the primary function of an intermediate coat? Barrier Protection 11. Which coating system is recommended for use on surfaces with an elevated temperature in a waste water treatment plant? Inorganic zinc primer/silicone topcoat 12. Mounting test panels containing candidate coating systems in the actual environment where the new coating will be installed is known as a facilityspecific performance evaluation. 13. Coatings contain two categories of ingredients: Non-volatile and Volatile. 14. Thinner addition increases the VOC content of a coating. 15. Prior to selecting a coating system, the facility owner must properly identify the prevailing service environment. A-18
PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 7 QUIZ ANSWER KEY
1. The primer used on connection points of I beams must often have a Class A or Class B slip coefficient if the connection is slip critical. 2. List four inspection concerns relating to application of primers on slip-critical connections. Primer thickness Amount of thinner used Type of thinner used Cure time prior to boling the connection 3. List three forms of metallized spray: Flame sray Arc spray Plasma spray 4. What is the minimum surface cleanliness and surface profile depth for metallizing applied to structures for marine or immersion service? SSPC-SP5; minimum 2.5 mil angular surface profile 5. Which form of metallizing feeds two wires to a spray gun? Arc spray 6. When measuring the thickness of thermal spray coatings on flat surfaces, a minimum of 5 readings are obtained in a line spaced 1 inch apart. 7. When measuring the thickness of thermal spray coatings on a complex geometry, a minimum of 5 readings are obtained in a 1.6 square inch diameter spot. 8. Powder coating may be cured using heat or ultraviolet (UV) light. 9. List seven inspection check points associated with powder coating application. Powder material Thickness Surface preparation Continuity Curing Hardness Appearance 10. Application of a liquid coating over a galvanized surface is known as a Duplex system. 11. Weathered galvanizing is optimum for coating, while new galvanizing is difficult to coat. 12. If “sweep blasting” of galvanizing is specified, the inspector may be required to measure the nozzle air pressure prior to sweep blasting operations. A-19
PCI Study Guide- October 2007
13. Most Type 1 and Type 2 DFT gages display the total thickness of the galvanizing and coating layers. 14. On overcoating projects, the inspector should verify that visible grease and oil contamination are removed prior to surface preparation. 15. Areas of sound coating adjacent to repair areas should be feathered to ensure a smooth transition for the new coating and to prevent lifting of the existing coating. 16. If a brush-off blast (SSPC-SP 7/NACE No. 4) is specified for an overcoating project, the inspector may be required to measure nozzle air pressure and verify proper abrasive type to ensure neither is too aggressive. 17. Pressure washing to remove dirt, chalking, etc. must be carefully inspected to ensure adequate removal prior to overcoating. 18. Prior to application of the overcoat material, an inspector should obtain thickness measurements on the existing coating. 19. The thickness of the overcoat can be isolated from the thickness of the existing coating by using a Tooke Gage. 20. List three toxic metals that may be in existing coatings: Lead Chromium Hexavalent Cadmium 21. A containment is designed to protect the environment and the public 22. Ventilation inside a containment is designed to protect workers. 23. SSPC Class 1 containment provides the highest level of protection. 24. Negative pressure is monitored visually or by reading a magnehelic gage. 25. Air flow inside a containment can be monitored using a rotating vane anemometer. 26. List two devices for monitoring air quality outside of a containment: Total Suspended Particulate (TSP) Particulate matter 10 microns and smaller (PM-10) 27. Pre- and post-project soil and/or water sampling and analysis may be required to verify effectiveness of the containment. 28. List three things a coatings inspector should never do inside a regulated area: Eat Drink Use tobacco products
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PCI Study Guide- October 2007
29. Hazardous waste can only be transported by licensed hauler. 30. List two SSPC Guides that govern containment and hazardous waste management procedures: Containment: SSPC Guide 6 Waste: SSPC Guide 7
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PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 8 QUIZ ANSWER KEY
1. List six possible causes of premature coating failure: Improper surface preparation Improper formulation Improper coating application Poor quality raw materials Improper coating system selection Design of the structure 2. List four consequences of coating failures: Substrate repair/replacement Downtime Costly rework Aesthetics 3. Describe how a coatings inspector can help prevent coating failures from occurring. By verifying that each step in the surface preparation and coating/lining installation process meets the requirements of the project specification. By identifying deficiencies as they occur and working with the contractor to bring the deficient areas into conformance with the specification before additional work progresses. 4. What key item maintained by an inspector is critical to a coating failure investigation? Thorough, complete, dated and signed inspection documentation
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PCI Study Guide- October 2007
SSPC PROTECTIVE COATINGS INSPECTOR (PCI) TRAINING MODULE 9 QUIZ ANSWER KEY
1. The coatings inspector shares in the responsibility for the safety of other workers and the public. 2. A coatings inspector that observes an imminent hazard that may cause death or serious injury should take immediate action to prevent the accident. 3. Who should an inspector obtain guidance from regarding their role relative to safety issues? Employer and/or counsel 4. List an example of a “General Risk” that a coatings inspector may be exposed to: Explosion; hazardous atmosphere; scaffold collapse; Inadequate hazard warnings around site 5. List an example of a “Personal Risk” that a coatings inspector may be exposed to: Entering a confined/hazardous space; falling; breathing in toxic metals 6. What is the primary difference between exposure hazards associated with inspection verses exposure hazards to painters? The magnitude or duration of exposure may be less for an inspector 7. List two “hazardous materials” that will be present on every coatings project: Solvents/thinners and coating components 8. The inside of a storage tank can be considered what type of “hazardous environment?” Confined space 9. Why is airless spraying categorized as a “hazardous activity?” High pressure and an injection hazard 10. The effect of hazardous materials on an inspector’s health depends on the level, duration and route of exposure. 11. List four items that are of the greatest value to an inspector on an MSDS: Health hazards (sign & symptoms of exposure) Primary routes of entry into the body Precautions of safe handling and use Controls measures and PPE 12. What is the most frequent way solvents affect the body? Skin contact A-23
PCI Study Guide- October 2007
13. Polyurethane coatings contain a chemical known as isocyanates, which are strong irritants and sensitizers. 14. Respirators equipped with HEPA filtration cartridges can filter respirable sizeddust. 15. Heights greater than six feet above a lower level require fall protection. 16. What type of lanyard is a component to a personal fall arrest system? Shockabsorbing 17. List three items that an inspector should verify before entering a confined space: Verify it has been tested and cleared for entry Proper personal protective equipment is employed Current training 18. What electrical hazard cannot typically be locked-out/tagged-out? Energized 3rd rails; overhead transmission wires 19. What hazard is associated with inadequate lighting? Trips and falls 20. List two basic types of respirators: Air purifying & Supplied air 21. Most coating inspection gages are not intrinsically safe and should not be used in hazardous environments.
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PCI Study Guide- October 2007 Appendix B
Glossary A Abrading. (1) Erosion by mechanical or particulate impact. (2) Surface preparation of concrete that is intended to roughen the surface profile and remove foreign materials. Methods classified as abrading include mechanical abrasion, waterjetting, and abrasive blast cleaning. Abrading methods are defined in ASTM D 4259. Abrasion Resistance. The ability of a coating to resist being worn away and to maintain its original appearance and structure when subjected to rubbing, scraping, or wear. [ASTM] Abrasive. (1) A material used for wearing away a surface by rubbing. (2) A fine, granulated material used for blast cleaning. Abrasive particles of controlled mesh sizes are propelled by compressed air, water, or centrifugal force to clean and roughen a surface. Blast cleaning abrasives often are simply referred to as metallic or non-metallic and as shot- or grit-like. [PCG] Abrasive Air Blast Cleaning. See Air Abrasive Blast Cleaning. Abrasive Blast Cleaning. Also called abrasive blasting, a surface preparation method that uses an abrasive propelled by air pressure, centrifugal force, or water pressure to clean and usually to profile a surface. Stand-off distance, angle of attack, and dwell time are the three most important variables under the control of an operator that can affect the quality and effectiveness of the blast cleaning. [PCG] Abrasive Blasting. See Abrasive Blast Cleaning. Abrasive Mix. Also called work mix or operating mix, the mixture of metallic or recyclable non-metallic abrasive sizes that results from the periodic addition of new abrasive to recycled abrasive during a blasting operation to maintain cleaning rate and surface profile. Abrasive Wheels. Metallic wheels mounted on a rotary power tool, commonly used to grind welds and remove weld spatter. Also used to remove rust and mill scale from localized areas. See Power Tool Cleaning. Accelerator. See Catalyst. Activator. See Catalyst. Adhesion. The degree of attraction between a coating and a substrate or between two coats of paint that are held together by chemical or mechanical forces or both. Adhesion often is called the “bonding strength” of a coating. Adhesion should not be confused with “cohesion,” which is the force holding a single coating layer together. [PCG] Adhesion Failure. A breakdown between two distinct coating layers or between the substrate and the first layer of coating. See Adhesion Test, Tensile (Pull-Off). Adhesion Test, Crosscut. Also called crosshatch test, a coatings adhesion test in which a crosshatch pattern is scribed onto the coated surface, then tape is applied and pulled off. Adhesion is assessed according to surface area from which flaking has occurred (ASTM
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PCI Study Guide- October 2007 D 3359). Adhesion measured by the crosscut test is referred to as the shear (or knife) adhesion. Adhesion Test, Tensile (Pull-Off). A method for testing the greatest perpendicular force that an area of coating can withstand before: (1) detaching from the surface (adhesion) or (2) fracturing within a layer of coating or substrate (cohesion). The method can also be used to determine whether a coating will remain intact at a particular applied tensile force. This standard test method is defined in ASTM D 4541. Aggregate. (1) A group of dry pigment particles held together by their surface forces; the spaces between the particles are filled with air. [CED] (2) Granular material, such as sand, gravel, crushed stone, crushed hydraulic-cement concrete, or iron blast-furnace slag, used with a hydraulic cementing medium to produce either concrete or mortar. [ACI] Air Abrasive Blast Cleaning. Also called abrasive air blast cleaning, a surface preparation method in which compressed air is used to propel abrasive particles against a surface to be cleaned. “Open blast cleaning” indicates that a localized containment does not surround the blast stream. “Closed blast cleaning” means that a localized containment does surround the blast stream. [PCG] Airless Spraying. A coating application method that uses hydraulic pressure instead of air to atomize paint by forcing it through a spray nozzle with a small orifice at a pressure of 2,000 to 3,000 psi (14-21 MPa). The spray pattern and flow of paint are controlled by the size and shape of the orifice. The size of the orifice must be matched with the viscosity of the paint and the size of the material pump. This process is aided if the material is previously heated. [PCG] Aliphatic. A class of organic hydrocarbon compounds composed of open chains. These include paraffins, olefins, etc. Alligatoring. Crazing or surface cracking with a definite pattern that looks like alligator hide. The effect is often the result of weather aging of a coating. See also Cracking. Ambient Conditions. The weather including: air temperature, relative humidity, dew point, and wind velocity, which are monitored on the job site. Amine. An organic compound derived from ammonia when one or more hydrogen atoms is replaced with hydrocarbon radicals. It is used as a curing agent for epoxy resins. Amine Blush. Surface opalescence (blush) on epoxy films caused by reaction of amine co-reactant with carbon dioxide and water to form an amine carbamate. Anchor Pattern. See Surface Profile. Anhydrous. Moisture-free; a compound without water of crystallization. [PCG] Anode. The electrode of an electrolytic cell at which oxidation occurs. Electrons flow away from the anode in the external circuit. It is usually at the anode that corrosion occurs and metal ions enter solution. Contrast with Cathode. [ASM] Anodized. An electrochemical protective or decorative oxide film. Anti-Fouling. A coating formulated to release noxious or poisonous substances at a controlled rate to prevent the growth of barnacles, algae, and other organisms on the underwater part of a ship hull. [PCG] Arcing. Spraying a coating with the gun moving in an arc, rather than at a constant distance from the substrate surface, so that a film of varying thickness results. Arcing may also occur with abrasive blasting to produce a variable level of surface cleaning. Arc Spraying. Metal spraying in which an electric arc is used to melt the metal.
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PCI Study Guide- October 2007 Aromatic. Hydrocarbon containing an unsaturated ring of carbon atoms, typified by the benzene ring structure. Xylene (xylol), toluene (toluol), and high-flash naphtha are aromatic solvents used in coatings.
B Ballast. Water stored in tanks on board ships to contribute to the trim and stability of the vessel. Ballast is pumped in and out from the sea to adjust the draft and distribute weight to control sag, hog, center of gravity, etc. This ballast can cause sweating on the exterior surface, which can contribute to coating failure Banana Gauge. An elongated magnetic dry film thickness gauge with a handle at one end and a probe at the other end. Between the handle and the probe is a positioning base and a thickness display dial. See Magnetic Gauge. Barometric Pressure. Atmospheric pressure, referenced in the U.S. Weather Bureau Psychrometric Tables. Used to aid in determining relative humidity and dew point, based on the dry and wet bulb readings from the psychrometer. Barrier Coat. (1) A coating or coating system that protects an underlying substrate by minimizing or eliminating the penetration of moisture or vapors. (2) A coating used to separate a layer of paint from a surface to prevent chemical or physical interaction. [PCG] Barrier Protection. See Barrier Coat. Base. (1) The major component of a multicomponent coating system. In two-component systems, the other component is usually called an “accelerator,” an “activator,” a “hardener,” or a “curing agent.” (2) A subfloor slab or “working mat,” either previously placed and hardened or freshly placed, on which floor topping is placed in a later operation; also the underlying stratum on which a concrete slab, such as a pavement, is placed. [ACI] Bend Test. See Flexibility Test. Binder. (1) Nonvolatile portion of the liquid vehicle of a coating. It binds or cements the pigment particles together and the paint film as a whole to the material to which it is applied. See Nonvolatile Vehicle. [CED] (2) Cementing material, either hydrated cements or products of cement or lime and reactive siliceous materials; the kinds of cement and curing conditions govern the general kind of binder formed; also materials such as asphalt, resins, and other materials forming the matrix of concretes, mortars, and sanded grouts. Biofouling. Biological encrustation of surfaces in sea water by flora and fauna, e.g., barnacles. Bisphenol A. Dihydroxydiphenyldimethylmethane, mol. wt. 224.1. Insoluble in water. Used in the manufacture of phenolic and epoxy resins. Condensation product formed by reaction of two (bis) molecules of phenol with acetone. This polyhydric phenol is a standard resin intermediate, along with epichlorhydrin, in the production of epoxy resins. [CED] Bisphenol A Epichlorohydrin. Chemical name of epoxy resin that is reacted with amines and other curing agents to form epoxy-based coatings.
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PCI Study Guide- October 2007 Bisphenol F. Dihydroxydiphenyldimethylmethane. Used in the manufacture of phenolic and epoxy resins. Condensation product of the reaction of two molecules of phenol with formaldehyde. Black Light. Popular term for ultraviolet (UV) radiation without any visible radiation.. [CED] Blast Pot. A container that holds abrasive material until it is mixed with compressed air in air abrasive blast cleaning systems. [PCG] Blasting Pressure. The pressure, usually expressed in pounds per square inch (PSI) or kiloPascals (kPa), of an air and abrasive mixture as it passes through the nozzle of an abrasive blasting system. Blistering. (1) The dome-shaped projections in paints or varnish films resulting from local loss of adhesion and lifting of the film from an underlying paint film (intercoat blistering) or the base substrate. The standard test method for evaluating the degree of blistering of paints is described in ASTM D 714. [PCG, V1] (2) The irregular raising of a thin layer at the surface of placed mortar or concrete during or soon after finishing, or in the case of pipe after spinning; also bulging of the finish plaster coat as it separates and draws away from the base coat. [ACI] Blotter Paper. Soft, spongy, absorbent paper. Blotter Test. The test for checking the cleanliness of compressed air supply as it reaches the blasting nozzle (described in ASTM D 4285). Blowdown. Removing dust from a surface with a stream of clean compressed air. Blushing. Film defect that appears as a milky opalescence as the film dries; can be a temporary or permanent condition. It is generally caused by rapid evaporation, moisture, or incompatibility. [CED] Bolted Connection. A mechanical fasting (connection) consisting of a threaded metal rod or pin (bolt) joined to a metal nut. Boottop. The area on the exterior hull of a ship between the light load line and the deep load line. The boottop will be fully immersed when the cargo is fully loaded and above water when the vessel is lightly loaded. This area is exposed to sun, wind, and water when light and to immersion when fully loaded. Bosun’s Chair. A rigging device suspended from a single cable or rope and designed for use by a single individual, who is limited to working in a sitting position. It allows access to high work areas and provides good maneuverability and accessibility to areas not easily reached by larger scaffolding systems. [PCG, V1] Boxing. Pouring paint from one container into another several times to assure that no unmixed material remains on the bottom and that the paint is uniformly mixed. [PCG] Breathing-Type Coating. A coating that is sufficiently permeable to permit transmission of water vapor without detrimental effect to itself. [CED] Bresle Sampler. A latex rubber cell that adheres to a surface, used to aid in the extraction of water-soluble surface contaminants. Brookfield Viscometer. A viscometer in which a cylinder or disk is rotated in a test liquid, and the torque necessary to overcome viscous resistance is measured. ASTM D 2196 covers the determination of the apparent viscosity and the shear thinning and thixotropic properties of non-Newtonian materials in the shear range of 0.1 to 50 s-1. [CED] Brush Blasting. See Brush-Off Blast Cleaning.
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PCI Study Guide- October 2007 Brush Down. To remove dust from a surface with a clean, soft brush. Brush-Off Blast Cleaning. Blast cleaning standard with the lowest quality requirements. According to SSPC-SP 7/ NACE No. 4, a brush-off blast cleaned surface is free of all visible oil, grease, dirt, dust, loose mill scale, loose rust, and loose paint. Tightly adherent mill scale, rust, and paint may remain on the surface. [PCG] Brushout. The application of paint on a small surface for testing. Bulkhead. (1) An upright partition or wall separating compartments, as in a ship’s hold. (2) Wall retaining soil along waterfront. Burnish. To polish or rub to a smoother or glossier surface. [CED]
C Cadmium. Toxic heavy metal. Cadmium compounds have been used as color pigments (e.g., orange, red, yellow) often mixed with other heavy metal compounds. Their use in coatings is restricted because of toxicity. Calcium Carbonate. A white crystalline substance used as an extender pigment. Also known as calcite, marble dust, carbonate of lime, English whiting, limestone, and cliffstone whiting. [PDC, PCG] Calibrate. To check, adjust, or determine by comparison with a standard. [CED] Calibration Plates. Precision plates used for calibrating magnetic dry film thickness gauges. Most commonly used standard plates are from NIST. Calibration Shims. Small color coded shims, usually plastic of various thicknesses that are used for calibrating Type II (fixed probe) magnetic dry film thickness gauges. Carbon Black. Finely divided carbon formed by any one of several processes. Synonym: gas black. These carbon blacks vary in particle size and some of them may be surface treated. [CED] Carcinogen. A material that either causes cancer in humans, or, because it causes cancer in animals, is considered capable of causing cancer in humans. [CED] Catalyst. A reaction promoter. A substance that induces, alters, or accelerates a chemical reaction. A true catalyst is unchanged by the reaction it creates. In the coatings industry, catalysts (also called activators, accelerators, and promoters) are used to speed the curing or crosslinking of certain coatings. Curing agents and hardeners (which enter into chemical reactions) are also sometimes (incorrectly) referred to as catalysts. [PCG] Cathode. The electrode of an electrolytic cell at which reduction is the principal reaction. (Electrons flow toward the cathode in the external circuit.) Typical cathodic processes are cations taking up electrons and being discharged, oxygen being reduced, and the reduction of an element or group of elements from a higher to a lower valence state. Contrast with Anode. [ASM] Cathodic Disbonding. Mechanical lifting of a coating caused by hydrogen bubbles formed when cathodic protection is excessive. Cathodic Protection. (1) Reducing the corrosion rate by shifting the corrosion potential of the electrode toward a less oxidizing potential by applying an external electromotive force. (2) Partial or complete protection of a metal from corrosion by making it a cathode, using either a galvanic or an impressed current. [ASM] Caustic. A strong chemical base. [CED]
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PCI Study Guide- October 2007 Centrifugal Wheels. Finned wheels on abrasive blasting equipment that pick up and hurl abrasive at high speeds onto the steel plates or shapes in a centrifugal blasting machine. See Abrasive Blast Cleaning. Chalking. (1) Formation of a friable powder on the surface of a coating film caused by the disintegration of the binding medium due to ultraviolet light breaking chemical bonds in the binder. The chalking of a coating film is dependent upon the binder and pigmentation, as well as the intensity of the ultraviolet light. The standard test method for evaluating degree of chalking is described in ASTM D 4214. (2) Formation of a loose powder resulting from the disintegration of the surface of concrete or of applied coating, such as cement paint. [ACI] Checking. (1) The development of breaks in the surface of a coating film that do not penetrate to an underlying coating or the substrate. If an underlying coating or the substrate is visible, the breaks are called “cracks.” Checking can be visible or microscopic. See also Cracking. The standard test method for evaluating degree of checking is described in ASTM D 660. [PCG, V1] (2) Development of shallow cracks at closely spaced but irregular intervals on the surface of plaster, cement paste, mortar, or concrete. [ACI] Chemical Resistance. The ability of a material to resist degradation by reaction with, dissolution by, or reduction of physical continuity from contact with a chemical agent or agents, thereby retaining its capacity to perform as a structural or aesthetic entity. The standard test method for chemical resistance of coatings is described in ASTM D 3912. Chemical Treatment Tanks. Tanks used for the storage of the various chemicals in either the water treatment or waste water treatment process. They may also be part of the process system as to where the chemicals are injected into the tanks as the water passes through them. Chilled Iron. A metallic abrasive prepared by channeling molten metal into streams, which then drop onto jets of water under pressure, atomizing the molten metal into random sizes of shot that fall into a water-filled quenching pit. Chipping. (1) Cleaning steel by removing paint or rust and scale, using a special “chipping” hammer. (2) Flaking deterioration of dried paint film, usually as a result of damage, impact, or wear. The ability of a coating or layers of coatings to resist total or partial removal, usually in small pieces, resulting from impact by hard objects or from wear during service. [PCG] (3) Treatment of a hardened concrete surface by chiseling. [ACI] Chloride Ion. Negatively charged ion (Cl-) derived from the element chlorine. Chromium. Metal with salts (chromates) that are sometimes used as pigments in primers for corrosion control. Clean Air Act. U.S. Congress legislation designed to protect ambient air from pollution. Closed Blast Cleaning. See Air Abrasive Blast Cleaning. Coalescence. The formation of a film of resinous or polymeric material when water evaporates from an emulsion or latex system, permitting contact and fusion of adjacent latex particles. Action of the joining of particles into a film as the volatile evaporates. Coal Tar. A dark brown to black cementitious material produced by the destructive distillation of bituminous coal. [ASTM] Coefficient of Thermal Expansion. Change in unit of length (or volume) accompanying a unit change of temperature, at a specified temperature. [ASTM]
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PCI Study Guide- October 2007 Cohesion. Propensity of a single substance to adhere to itself; the internal attraction of molecular particles toward each other; the ability to resist partition from the mass; internal adhesion; the force holding a single substance together. [CED] Cohesion Failure. A failure or break within a given coat or material (the coating breaks within itself). See Adhesion Test, Tensile (Pull-Off). Coin Rub Test. A method of testing the cure of inorganic zinc-rich coatings. Combustible. Capable of burning. Combustible liquids are those having a flash point at or above 140°F (60°C). Commercial Blast Cleaning. Moderate grade of blast cleaning. According to SSPC-SP 6/NACE No. 3, a commercial blast cleaned surface is free of all visible oil, grease, dirt, dust, mill scale, rust, paint, oxides, corrosion products, and other foreign matter; staining is limited to no more that 33 percent of each unit area of surface. [PCG] Comparator. See Surface Profile Comparator. Compressive Strength. (1) Maximum compressive stress that a material is capable of developing. [CED] (2) The measured maximum resistance of a concrete or mortar specimen to axial compressive loading; expressed as force per unit cross-sectional area; or the specified resistance used in design calculations. [ACI] Conductimetric Analysis. Chemical analysis made by determining the electrical conductivity of a solution. Conductive. Able to conduct electricity or heat. Conductivity. See Electrical Conductivity. Conductivity Meter. Field or laboratory instrument for measuring total electrical conductivity of an aqueous solution. Confined Space. An area that may be hazardous because a limited number of openings could make escape difficult in an emergency, and because ventilation may be inadequate to support life. The space may also present unknown hazards such as toxic or caustic chemicals. The legal definition of a confined space (29 CFR 1910.146) is one that is large enough and so configured that an employee can bodily enter and perform assigned work; has limited or restricted means for entry or exit (for example, tanks, vessels, silos, storage bins, hoppers, vaults, and pits); and is not designed for continuous employee occupancy. Constant Pressure Probe Gauge. See Magnetic Fixed Probe Gauge, Type 2. Contact Thermometer. A magnetic thermometer that is placed directly onto the steel surface to determine surface temperature. See also Non-Contact Thermometer. Containment. (1) A method to limit dust, debris, paint chips, paint dust, spent abrasives, and overspray from contaminating the environment. The type, concentration, and toxicity of the contamination determines the extent of containment required. Typical types of containment systems include free-hanging enclosures, partial structure enclosures, and total structure enclosures with or without negative pressure. [PCG] (2) Hermetically sealed portion within the reactor building of a nuclear power plant that contains the nuclear reactor. Conversion Coating. A treatment, either chemical or electrochemical, of the metal surface to convert it to another chemical form that provides an insulating barrier of exceedingly low solubility between the metal and its environment, but which is an integral part of the metallic substrate. [CED]
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PCI Study Guide- October 2007 Convertible Coating. Irreversible transformation of a coating after its film formation to a film insoluble in the solvent from which it was deposited. This should not be confused with chemical conversion coating. See Thermosetting. [CED] Co-Reactant. One of two or more chemical materials formulated to react with each other to produce a desired end product. Cosolvent. A solvent, sometimes called a coupling agent, that allows the mixing of two immiscible liquids. [PCG, V1] Couplant. A substance used between the probe and test surface to permit or improve transmission of ultrasonic energy through an ultrasonic thickness gauge. Coupling Agent. See Cosolvent. Cracking. (1) The splitting of a dry coating film, usually the result of continuing curing or aging that causes the film to become hard and brittle. Different types of cracking include hair-cracking or hairlines, checking, cracking, crazing, crocodiling or alligatoring, and mud cracking. The standard test method for evaluating degree of cracking is described in ASTM D 661. (2) To break up into simpler chemical components, as with cracking of petroleum Crevice. A narrow opening; fissure. Crosscut Adhesion Test. See Adhesion Test, Crosscut. Crosshatch Test. See ADHESION TEST, CROSSCUT. Crosslinking. Applied to polymer molecules, chemical links between the molecular chains that form a three-dimensional or network polymer generally by covalent bonding. [CED] Curing. (1) The process by which a coating changes from a liquid state into a dry, stable, solid protective film. Curing may involve chemical reaction with oxygen, moisture, or chemical additives, or the application of heat or radiation. (2) Maintaining satisfactory moisture content and temperature in concrete during its early stages so that desired properties may develop. [ACI] Curing Agent. An additive component, sometimes called a hardener or (incorrectly) a catalyst, that helps a coating film or concrete cure by chemical reaction. Compare Catalyst. Curing Compound. A liquid that can be applied as a coating to the surface of newly placed concrete to retard the loss of water or, in the case of pigmented compounds, also to reflect heat so as to provide an opportunity for the concrete to develop its properties in a favorable temperature and moisture environment. [ACI] Cut Back. A solution of a coating binder material (e.g., coal tar or asphalt) in an organic solvent to provide easy application of a film.
D dB. See Decibel. DBA. See Design Basis Accident. Dead Man’s Control. Safety cut-out device at blast nozzle connected to pressure relief valve on blast-pot (blast-kettle). May be air operated or electrical. Dechlorination. In wastewater treatment plants, treatment to reduce the chlorine level of the effluent water before it is discharged. This can be done by injecting the effluent with sulfur dioxide gas (at a 1:1 ratio to the amount of chlorine injected previously) as it leaves
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PCI Study Guide- October 2007 the chlorine contact basins. Dechlorination is then completed by aerating the water either through a cascade system or air injection. Decibel. Abbreviated dB, unit of measurement for sound intensity. Delamination. (1) The separation of a layer or layers of coating from the previous layer or from the substrate. Failure of a coating to adhere to the previous coating. (2) In the case of a concrete slab, a horizontal splitting, cracking, or separation of a slab in a plane roughly parallel to, and generally near, the upper surface; found most frequently in bridge decks and caused by the corrosion of reinforcing steel or freezing and thawing; similar to spalling, scaling, or peeling except that delamination affects large areas and can often only be detected by tapping. [ACI] Density. A measure of mass per unit volume. The density of paint usually is expressed as pounds per gallon or kilograms per liter. [PCG] Depth Gauge. Instrument for measuring depth of a pit or crevice. Depth Micrometer. See Depth Gauge. Destructive Dry Film Thickness Gauge. See Dry Film Thickness Gauge, Destructive. Detachment. See Delamination. Detergent Cleaning. Removing contamination from a surface using an aqueous solution of a surface-active agent. De-Watering. (1) Term describing a type of accident in a nuclear power plant in which water spills from the system to the extent that the fuel in the reactor is no longer immersed. (2) Removing water from drydocks, locks, or other containments. Dew Point. That temperature at which water pressure present in the atmosphere is just sufficient to saturate it. When air is cooled below the dew point, the excess of water vapor appears as tiny water droplets or crystals of ice depending on the temperature of the air mass. [IUPAC, CED] DFT. See Dry Film Thickness. Disbonding. Failure of a coating to adhere to a substrate to which it is applied. Intercoat disbonding is the failure of a coating to adhere to a previous coating layer or to the substrate to which it has been applied. Intracoat disbonding is the failure of a coating layer to cohere or hold itself together. See Adhesion, Cohesion. Discontinuity. See Holiday. Dissimilar Metal Corrosion. See Galvanic Corrosion. Dolly. See Pull Stub. Double Rub. The act of rubbing a solvent saturated cloth in one complete forward and backward motion over the coated surface. [CED] Dry Bulb Temperature. The temperature recorded by the dry bulb thermometer of a psychrometer. [PCG] Dry Bulb Thermometer. The thermometer on a sling or other psychrometer with a bulb is directly exposed to the air (i.e., not covered with a wet sock). See Psychrometer. Dry Film Thickness (DFT). Depth of cured film, usually expressed in mils (0.001 inch) or micrometers (millionths of a meter). Standard methods for measuring dry film thickness are defined in SSPC-PA 2, ASTM D 1005, ASTM D 1186, and ASTM D 1400. Dry Film Thickness Gauge. An instrument used to measure the dry film thickness of a coating.
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PCI Study Guide- October 2007 Dry Film Thickness Gauge, Destructive. Instrument used to determine dry film thickness as described in ASTM D 4138. It is capable of measuring the thickness of individual coating layers. Dry Film Thickness Gauge, Eddy Current. A dry film thickness gauge that measures the thickness of non-conductive coatings on non-ferrous metal substrates. Dry Film Thickness Gauge, Magnetic. See Banana Gauge; Magnetic Fixed Probe Gauge, Type 2; Magnetic Pull-Off Gauge, Type 1; and Pencil-Type Pull-Off Gauge. Drying Oil. An oil that possesses to a marked degree the property of readily taking up oxygen from the air and changing to a relatively hard, tough substance when exposed in a thin film to the air. [ASTM] Dry Spray. (1) A rough, powdery, non-coherent, discontinuous film produced when an atomized coating partially dries before reaching the surface. (2) Overspray or bounce back falling dry on unintended surfaces and producing an adherent, sand-like covering. [PCG] Ductility. Tendency of a material to undergo deformation and extension without cracking or splitting. [CED] Durability. A term indicating degree of permanency, used to describe individual properties, such as the gloss, or general characteristics. [PCG] Durometer Hardness. An arbitrary numerical value that measures how well as surface resists indentation by the durometer’s blunt indentor point. The value may be taken immediately or after a very short specified time. [ASTM] Durometer. Instrument for measuring the surface hardness of rubber, plastic, or protective coatings. [CED]
E Eddy Current Gauge. See Dry Film Thickness Gauge, Eddy Current. Eddy Current Testing. Determining a coating dry film thickness on certain metals by measuring opposing electrical (eddy) currents produced by the gauge. Edge Failure. Undercutting (penetration of corrosion underneath the coating) as it occurs at an unprotected or incompletely protected edge. Edge retention. Percent of coating after application that remains on an edge as compared to that remaining on a flat surface. Edge-Retentive Coating. Coating with at least 70% edge retention. Effluent. Any spent liquors or other waste material that are emitted by a source (waste from plating shops, pickling tanks, sewage treatment plants, chemical manufacturing plants, etc.). [IUPAC, CED] Elastomeric. Rubberlike; relating to or having the properties of elastomers. [CED] Electrical Conductivity. The property of a fluid or solid that permits the passage of an electrical current as a result of an impressed electromagnetic field. It is measured by the quantity of electricity transferred across unit area per unit potential gradient per unit time. (In sampling and analysis, changes in this property are utilized to measure the presence of certain ions and compounds such as sulfur dioxide.) [ASTM] Electric Arc Gun. A type of thermal spraying equipment in which a metal wire is melted continuously by electric arc and then atomized by an air jet. An electric arc gun is less
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PCI Study Guide- October 2007 maneuverable than an oxy-fuel gas gun, but the deposit rate of the metal is two to three times greater. See Thermal Spraying. [PCG] Electrostatic Precipitator. An electrical device used to attract and separate suspended particles from an exhaust system Electrostatic Spraying. A method of applying a spray coating in which charged coating particles are attracted to a grounded, conductive substrate. The mist travels around corners of the substrate with the result that the article is coated more uniformly on all sides and edges with very little overspray and bounce back. [PCG] Elongation. A method of measuring coating flexibility; the increase in specimen length from the point of initial load application to the point of film rupture in a tension test. ASTM D 2370 covers the measurement of elongation as well as tensile strength and stiffness (modulus of elasticity) of organic coatings when tested as free films. [ASTM, CED] Emulsion. Two-phase liquid system in which small droplets of one liquid (the internal phase) are immiscible in, and are dispersed uniformly throughout, a second continuous liquid phase (the external phase). [CED] Emulsion Coating. A coating in which the vehicle is an emulsion of binder in water. The binder may be oil, oleoresinous varnish, resin, or another emulsifiable binder. Not to be confused with a latex paint in which the vehicle is a latex. [CED] Enamel. A finish coat that dries to a smooth, gloss surface. [PCG] Encapsulation. The process of enclosing a surface, especially of one containing hazardous materials, on all sides. Encapsulants include drywall, fiber-filled coatings, wood, or other materials. [PCG] Engineering Standard. A document that provides options for construction work such as coating different types of structures. Epichlorhydrin. A chemical used in the production of epoxy resins. Exothermic Reaction. Chemical reaction that produces heat. Expansion Dam. The part of an expansion joint serving as an end form for placing concrete at a joint. Also applied to the expansion joint device itself. Expansion Joint. (1) A separation provided between adjoining parts of a structure to allow movement where expansion is likely to exceed contraction. (2) A separation between pavement slabs on grade, filled with a compressible filler material. (3) An isolation joint intended to allow independent movement between adjoining parts. [ACI] Exposure. Placing a specimen in test conditions. [PCG]
F Fabricated Structural Steel. Steel members made by fastening steel shapes such as plates and angles, together by riveting, bolting, or welding. Feather Edging. (1) Reducing the thickness of the edge of a dry paint film, such as the edge of a damaged area, by sanding or rubbing down prior to repainting. (2) Tapering the edges of a coat of wet paint by laying off with a comparatively dry brush. [MPDA, PCG] Ferrous. (1) A chemical compound that contains iron in the bivalent (2+) state. (2) Any metal alloy based primarily on iron. [PCG] Fiberglass. Glass in fibrous form used to provide reinforcement or other desirable properties to a variety of products such as coatings and linings.
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PCI Study Guide- October 2007 Fiberglass-Reinforced Plastic (FRP). Resin linings, usually polyester, vinyl ester, or epoxy, into which layers of fiberglass are incorporated to optimize the lining’s performance. The abbreviation “FRP” is also used for “fiber-reinforced plastic,” a general term for a composite that is reinforced with cloth, mat, strands, or any other fiber form. Field Standard. A quality control reference product (e.g., surface) used for comparison to construction work at the job site. Filler. (1) A thick, pigmented material used to fill holes, defects, or pores in a surface before coating. See also Block Filler. [PCG] (2) Finely divided inert material such as pulverized limestone, silica, or colloidal substances sometimes added to Portland cement or other materials to reduce shrinkage, improve workability, or act as an extender. (3) Material used to fill an opening in a form. [ACI] Fineness of Grind. A numerical assessment of the degree of pigment dispersion in the vehicle of a coating, or of the presence of coarse particles in pigmented coatings as determined by the protrusion of particles or agglomerates through the wet film at a given thickness. [CED] Fines. Finely crushed or powdered material, such as blasting abrasive residues. Finish. (1) Final coat in a paint system. (2) Sometimes refers to the entire coating system: the texture, color, and smoothness of a surface, and other properties affecting appearance. [CED] (3) The texture of a concrete surface after compaction and finishing operations have been performed. Finishing. Leveling, smoothing, consolidating, and otherwise treating surfaces of fresh or recently placed concrete or mortar to produce desired appearance and service. [ACI] Fixed Probe Gauge. See Magnetic Fixed Probe Gauge, Type 2. Flake-Filled. A coating filled with micaceous iron oxide or another pigment that increases its barrier protection properties. Flame Spraying. The spray application of a coating whereby metal wire, metallic powder, or thermoplastic powder is melted using a spray gun with a torch-like flame and then sprayed with compressed air. See also Metallizing, Plasma Spraying, and Thermal Spraying. [PCG] Flammability. Those characteristics of a material that pertain to its relative ease of ignition and relative ability to sustain combustion. [ASTM] Flash Point. The lowest temperature of a liquid at which it gives off sufficient vapor to form an ignitable mixture with the air near the surface of the liquid or within the vessel used. [CED] Materials with flash points below 100°F (38°C), such as most solvents and solvent-borne coatings are considered dangerous. The standard method for flash point is defined in ASTM D 3941. [PCG] Flash Rusting. Rusting that occurs on metal within minutes to a few hours after blast cleaning or other cleaning is complete. The speed with which flash rusting occurs may be indicative of salt contamination on the surface, high humidity, or both. [PCG] Flexibility. Degree to which a coating after drying is able to conform to movement or deformation of its supporting surface, without cracking or flaking. [CED] Flexibility Test. Test applied to cured films to determine if they are able to elongate without fracture or disbondment. Syn: Bend test. [CED] See Elongation. Flint Abrasive. Not flint at all, but actually a natural quartz (silicon dioxide) that fractures into sharp-edged grains and is used on the common sandpaper for wood. [CED]
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PCI Study Guide- October 2007 Flocculent. Having a loose, fluffy organization resembling wool. Used to describe degree of pigment suspended in paint vehicle. Fluid Tip. The removable end of an air-spray gun from which the atomized paint is sprayed and in which the needle is seated. The fluid tip works in conjunction with the needle to regulate the flow of fluids before they are atomized. [PCG] Fluidized Bed Coating. Method of applying a coating in which a heated or electrostatically charged article is immersed or passed over a fluidized bed of powdered coating (the coating material adhering to the hot metal), then fused in an oven to provide a smooth, continuous film. [CED] Fluorescence. Optical phenomenon characterized by the reemission of absorbed radiant energy by certain chemicals or materials. [CED] Foot Candle. Unit of illumination equal to one lumen per square foot. [ASTM] The preferred unit of illumination is the SI unit lux (one lumen per square meter). Form Release Agent. Compound such as petroleum oil, wax, and silicone applied to concrete forms to allow easy removal from poured concrete after it has cured. [PCG] Freezer Room. A room where food or food ingredients are kept frozen, usually between 32 and -15°F (0 and -8°C). FRP. See Fiberglass-Reinforced Plastic. Fusion Bonded Epoxy (FBE). A powder coating commonly applied to pipelines, rebar, etc., for corrosion control.
G Galvanic Corrosion. Accelerated metal corrosion that occurs because of an electrical contact with a more noble metal or nonmetallic conductor in a corrosive electrolyte. [ASM] The term “dissimilar metal corrosion” is sometimes used when appropriate. Galvanic Protection. (1) The selective use of galvanic corrosion to protect one metal from deterioration by connecting it to another, more active (electrically negative), sacrificial metal. Both metals must be in contact with the same body of an electrolytic solution. Zinc, magnesium, or aluminum can be used as sacrificial metals for the galvanic protection of steel. (2) Protecting a metal in contact with an electrolytic solution from corrosion by the use of an impressed direct electrical current. (3) Protecting steel with zinc-rich coatings. [PCG] See Cathodic Protection. Galvanizing. Applying a zinc coating to steel by dipping it in molten zinc or by depositing zinc on the steel electrolytically or mechanically. [PCG] Gel Time. The period from the initial mixing of the reactants of a liquid material to the time when gelation occurs, as defined by a specific test method. [ASTM] Generic. (1) Belonging to an entire class or group. (2) Non-proprietary. [PCG] Gloss. The degree to which a surface reflects visual images. It is a direct function of coating formulation and the amount and size of pigment particles in the coating, the more pigment particles and the larger the diameter, the lower the gloss. [PCG] Gouge Hardness. In determining coating hardness by pencil testing (ASTM D 3363), the hardest pencil that will leave the film uncut. See also Scratch Hardness. Grit. (1) An angular material with sharp, irregular edges obtained from slag, steel, minerals, and various other materials for use as a blast cleaning abrasive. (2) Small, hard foreign particles sometimes found in paint and coating materials. [PCG]
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PCI Study Guide- October 2007 Grit Blasting. See Abrasive Blast Cleaning. [PCG]
H Hackle. Thin, needle-like or sliver-like protrusions, ranging from 3 to 6 mils (75 to 150 micrometers), found on steel plates that have been blast cleaned with steel shot or grit. [PCG] Hand Tool Cleaning. The use of manually operated impact, scraping, sanding, and brushing tools to remove loose paint, rust, and mill scale. Such tools include slag hammers, chipping hammers, scrapers, and wire brushes. The specification SSPC-SP 2, Hand Tool Cleaning, is a consensus standard covering the procedures necessary for handtool cleaning of steel surfaces. [PCG] Hardener. (1) Chemical agent used to promote or control the hardening or curing reaction in coating or resin systems. See Curing Agent. (2) A chemical (including certain fluosilicates or sodium silicate) applied to concrete floors to reduce wear and dusting. [ACI] Hardness. The property of a coating that allows it to resist damage or abrasion. [PCG] Hardness Testing, Pencil Method. A method of testing coating hardness that uses a series of lead pencils to determine which pencil will not cut through the coating and which pencil will not scratch the coating. The hardest pencil that will leave the film uncut defines the gouge hardness; the hardest pencil that will not scratch the film defines the scratch hardness. This method is defined in ASTM D 3363. Hazardous Waste. A solid waste, including liquid waste, that exhibits: ignitability, corrosivity, reactivity, or toxicity, as defined in 40 CFR 261, “Identification and Listing of Hazardous Waste,” or that is on a special list established by EPA. [ILPR, PCG] HAZCOM. U.S. regulations governing hazardous chemicals in the workplace, issued by OSHA in 1983; also known as the “Right-to-Know” regulations. The purpose of HAZCOM is to ensure that workers are informed about chemical hazards in the workplace, and that they are provided with information and training in how to safely handle these chemicals. Heat Resistance. The ability of a coating to resist deterioration when exposed continuously or periodically to high temperatures at or below a given level, which depends on the binder type and other coating ingredients. [PCG] Heat-Shrink Sleeve. Cover, frequently polyethylene, that is placed around a structural component, such as a pipe weld joint, and shrunk in place by heating. Heavy Metal. Metallic element of high molecular weight, compounds of which are often toxic. Hiding Power. The ability of a coat of paint that has been properly applied to obscure (hide) a surface or a previous coating on the surface. [PCG, V1] High-Solids-Coating. A coating with a high non-volatile content. Currently, 70% solids by volume is used as a benchmark measurement, at or beyond which a coating is said to be high solids. Many new coatings contain no solvent and are called 100% solids coatings. Hog. The upward curvature of a ship’s bottom. Hold Point. Critical point in an operation where work is stopped until the work to date has been approved.
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PCI Study Guide- October 2007 Holiday. Application defect whereby a small area is left uncoated. Synonyms: miss, skip, void, discontinuity, vacation. [CED] Holiday Detector, High-Voltage. Also called a spark tester, an instrument for detecting holidays in a nonconductive coating applied over a conductive substrate. A spark test instrument applies a voltage to the surface with a probe that creates a spark whenever a holiday, pinhole, or other defect is found. The spark triggers an alarm or light on the instrument. The voltage used depends on the coating and thickness. Holiday Detector, Low-Voltage Wet Sponge. An instrument that uses 5-90 volts DC to detect holidays in a coating. It is typically used for films of less than 20 mils (510 micrometers) dry film thickness. Holiday Test. Test for detecting small areas of paint film that are incompletely coated (holidays). Standard methods for holiday testing are defined in ASTM D 5162, ASTM D 4787, and NACE RP0188-90. Hot Flocking Method. A method of powder coating application that relies on a nonelectrostatic spray of powder onto parts that have been preheated above the softening point of the powder. The powder melts and clings to the preheated parts. In some cases, the coating is fused/cured by residual heat in the parts, while in others, a post-heating step is required. Hot Spraying. Spraying hot lacquers or paints, the viscosities of which have been reduced to spraying consistency by means of heat instead of by adding volatile solvents. By such a process, it is possible to apply materials with higher-solid content and therefore better build. [CED] Hull. The frame or body of a ship exclusive of masts, deck houses, superstructure, and rigging. Hydraulic Adhesion Test Equipment (HATE). Commercial hydraulic instrument for determining coating adhesion to a substrate by the pull-off method. See Adhesion Test, Tensile (Pull-Off). Hydroblasting. A cleaning process in which pressurized water is directed through a nozzle to impact a surface. The term is used generically to describe cleaning with water without abrasives from low pressure water cleaning to ultra-high pressure waterjetting. See also Hydrojetting and Waterjetting. Hydrocarbon Solvent. Aliphatic, aromatic, or cyclic (cycloparaffinic, naphthenic) solvent containing only carbon and hydrogen. [PCG] Hydrochloric Acid. An aqueous solution of hydrogen chloride gas. Dissolves many metals, forming chlorides and liberating hydrogen. Used extensively in industry for numerous purposes including concrete surface preparation. Hydrojetting. A generic term describing the process in which pressurized water is directed through a nozzle to impact a surface. See also Hydroblasting and Waterjetting. Hydrolasing. A term commonly used for high or ultra-high pressure water blasting. See Waterjetting and Hydrojetting. Hydrolysis. Chemical reaction consisting of splitting a compound into two parts, one of which combines with the H+ ion of water, and the other combines with the OH- ion of water. [CED] Hygrothermograph. An instrument for measuring and recording the air temperature and relative humidity.
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PCI Study Guide- October 2007 Hypodermic Pressure Gauge. A gauge with a hypodermic needle that is inserted into the hose at various locations (e.g., just before the nozzle used with abrasive blasting equipment) to determine air pressure.
I Immersion-Grade Coating. A coating suitable for use during immersion in water or other liquids. Immersion Service. Use of a coating under water or another liquid; in this service, the coating is frequently called a lining. [PCG] Impact Resistance. Ability of a coating to resist a sudden blow; ability to resist deformation from impact. [PCG] Impact Strength. Resistance to damage from collision with another body. Impressed Current Cathodic Protection. Cathodic protection applied with an external DC power source. See Cathodic Protection. [ASTM] Indicator. Reagent used in chemical analysis that changes in color as the chemical environment changes. Induction Time. Sometimes called sweat-in time, the interval that must elapse after mixing the components of multicomponent paint before application can begin. [PCG] Infrared (IR). Invisible part of the electromagnetic spectrum between radio waves and the red portion of visible light, with wavelengths between 0.78 and 1.0 micrometer (780 to 1,000 nanometers). It produces a heating effect on impact with an absorptive surface, and sometimes is used to cure coatings. Infrared radiation is also used to chemically characterize materials in infrared spectroscopy. [PCG] Inhibitive Pigment. A pigment that when formulated into a coating provides active corrosion inhibition to a metal substrate or inhibits some other undesirable effect. [PCG] Inhibitive Primer. Primer containing inhibitive pigment or other chemical material. Inhibitor. (1) General term for compounds or materials that slow or stop an undesired chemical reaction, such as oxidation, corrosion, drying, skinning, mildew growth, etc. (2) In wet cleaning methods for steel, a material that can be added to the water or applied as a rinse to prevent flash rusting. [PCG] Initial Condition. See Rust Grade. Initiator. See Catalyst. Intercoat Adhesion. The ability of one coat of paint to adhere to the next. [PCG] Intrinsically Safe. Electrical equipment designed to separate sparking from the external environment, so that the equipment can be used in hazardous environments. Intumescent Coatings. A fire-retardant coating that when heated forms a foam produced by non-flammable gases, such as carbon dioxide and ammonia. This results in a thick, highly insulating layer of carbon (about 50 times as thick as the original coating) that serves to protect the coated substrate from fire. [ASTM] Ionic Contaminants. See Soluble Salt Contaminants. Isocyanate. A compound containing one or more of the chemical group -N=C=O. Isocyanates comprise one major component of two-component polyurethane coatings. When the isocyanate groups are crosslinked with a hydroxyl-containing material (polyol), a polyurethane polymer is formed; when combined with a amino-containing material, a polyurea polymer is formed. [PCG]
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PCI Study Guide- October 2007
J Job Specification. Written, legal document, usually part of a contract, that precisely describes an item of work that is to be accomplished. See also Specification.
K Knife Adhesion. See Adhesion Test, Crosscut.
L Lacquer. Coating composition based on synthetic thermoplastic film-forming material dissolved in organic solvent, which dries primarily by solvent evaporation. Typical lacquers include those based on nitrocellulose, other cellulose derivatives, vinyl resins, acrylic resins, etc. They are re-soluble in their original solvent. [CED] Laitance. A layer of weak and nondurable material containing cement and fines from aggregates, brought by bleeding water to the top of overwet concrete; the amount is generally increased by overworking or over-manipulating concrete at the surface by improper finishing or by job traffic. [ACI] Laminar. Arranged in, consisting of, or resembling thin plates or scales. Laminations. Relatively large surface flakes, scales, or layers that are formed on steel during the rolling process. [PCG] Latex. A coating containing a stable aqueous dispersion of synthetic resin, produced by emulsion polymerization, as the principal constituent of the binder. Modifying resins may also be present. [ASTM] Lattice. A framework of cut lines used in adhesion testing. See Adhesion Test, Crosscut. Lead. A heavy metal. Lead compounds have been used extensively in the past as hiding pigments and/or inhibitive pigments. It is hazardous to health if breathed or swallowed, causing mental retardation in children and dangers to workers generating lead-containing dust. Residential use of lead-containing paint pigments has been eliminated in the United States, and industrial use has been greatly reduced. Lead-Containing Paint. There is no consensus definition for lead-containing paint in industrial maintenance applications. The following definitions have been developed for related applications: (1) Consumer Products: A paint or other, similar surface coating in which the lead content (calculated as lead metal) exceeds 0.06 percent by weight of the total non-volatile content of the paint or the weight of the dried paint film. The 0.06 percent level is equivalent to 600 ppm. [ILPR] (2) Residential Use: A paint that contains at least 0.5 percent lead by weight of the dried paint film. The 0.5 percent level is equivalent to 5000 ppm. [PCG] Leafing. Particles of certain metallic and other pigments in the form of thin flat flakes in aligning themselves with or floating on or near the surface of the vehicle. [CED] LEL. See Lower Explosive Limit.
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PCI Study Guide- October 2007 Leveling. A coating’s ability to flow out on a surface so that brush or roller marks or other irregularities produced during application are not apparent. [PCG] Leveling Agent. Chemical added to coating to increase the ability of the wet film to settle to a uniform thickness. LFL. See Lower Flammable Limit. Limpet (Soltz) Cell. A rigid cell used to collect soluble salt from a contaminated surface in order to determine its concentration. Line of Demarcation. On ships, the line of demarcation is where the above-water paint system meets the underwater paint system. It is usually the deep load line or draft line on the vertical sides of the ship. Line Travel Machine. A machine that performs one of the cleaning or coating processes while moving continuously on wheels or another means along the length of the pipeline. Lining. (1) A material used to protect a container against corrosion and/or to protect the contents of the container from contamination by the container shell material. Sprayable linings, sheet liners, and drop-in liners can be used for this. [PCG] (2) Any sheet, plate, or layer of material attached directly to the inside face of formwork to improve or alter the surface texture and quality of the finished concrete. [ACI] Litmus Test. The use of litmus or pH paper to measure the acidity or alkalinity (pH) of a water solution. [PCG] Loading Fixture. A component of an instrument (e.g., an adhesion tester) to which a force (load) is applied to determine a physical property such as bonding strength. Lockout. A means of protecting workers from injury or death caused by the accidental start-up or release of stored energy from equipment. It involves blocking the flow of energy from the power source to the piece of equipment with a padlock or chain, or by removing a component such as a fuse or circuit breaker. See also Tagging. Lower Explosive Limit (LEL). The concentration, at ordinary ambient temperatures, of a compound in air below which an explosion will not occur if the mixture is ignited. The concentration is expressed as a percent of the gas vapor in air by volume. When the concentration of a substance in air is above the lower explosive limit and below the upper explosive limit (UEL), the mixture will burn and explode. [PCG] Lower Flammable Limit (LFL). The minimum concentration of a combustible substance that is capable of propagating a flame through a homogeneous mixture of the combustible and a gaseous oxidizer under the specified conditions of test. [ASTM]
M Magnetic Base Reading (MBR). The measurement obtained when placing a dry film thickness gauge on a magnetic substrate that has been blast cleaned. Magnetic Fixed Probe Gauge, Type 2. A dry film thickness gauge that operates with changes in magnetic flux within the probe or the instrument. The magnitudes of these changes are an inverse (nonlinear) function of the distance between the probe and the steel surface under the paint. Type 2 refers to the gauge’s designation in SSPC-PA 2. Magnetic Gauge. See Dry Film Thickness Gauge, Magnetic. Magnetic Pull-Off Gauge, Type 1. A dry film thickness gauge that uses a spring balance to pull a small permanent magnet from the surface of the painted steel. The magnetic force holding to the surface varies inversely as a non-linear function of the distance
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PCI Study Guide- October 2007 between magnet and steel, i.e., the thickness of the dry paint film (plus any other films present). Type 1 refers to the gauge’s designation in SSPC-PA 2. Mandrel. In bend testing, the tool used to control the strain on the concave side of a bend in a wrap-around bend test and also to apply the bending force in a semi-guided or guided bend test. [ASTM] Manufacturer’s Technical Data Sheet. Product instructions and information. Mastic. (1) A high-build coating. (2) An adhesive material. [PCG] Material Safety Data Sheet (MSDS). OSHA’s established guidelines for the descriptive data that should be concisely provided on a data sheet to serve as the basis for written hazard-communication programs. The thrust of the law is to have those who make, distribute, and use hazardous materials be responsible for effective communication. [CED] MBR. See Magnetic Base Reading. Mechanical Adhesion Testing. Adhesion testing performed with a pull-off instrument. An aluminum pull stub (loading fixture) is bonded onto a coated surface. After the bonding adhesive cures, the force on the pull stub is continuously increased and monitored until it detaches or until a specific force is attained (ASTM D 4541; Annex A.1). MEK. See Methyl Ethyl Ketone. Mercury. A toxic heavy metallic element that is liquid at usual temperatures. Mercury compounds have been used extensively in the past in paints as mildewcides. The toxicities of these products vary depending upon the chemical compound in which they occur. Metallizing. Spraying a coating of metal onto a surface. See also Flame Spraying, Plasma Spraying, and Thermal Spraying. [PCG] Metal Spray Coating. A film of molten metal, often zinc or aluminum, dispersed (sprayed) onto a surface, such as steel, for corrosion control. Methyl Ethyl Ketone (MEK). A low-boiling strong solvent, similar to acetone but less volatile. [PCG] Methyl Ethyl Ketone Peroxide. A chemical used in small amounts to accelerate the curing of polyester coatings. Methyl Isobutyl Ketone (MIBK). A medium-boiling strong solvent. [PCG] Microbiologically Influenced Corrosion (MIC). Corrosion that is affected by the action of microorganisms in the environment, e.g., sulfate-reducing bacteria found in some petroleum products and in sewage. Micrometer. (1) One millionth of a meter, abbreviated as µm. Also sometimes called a micron. Coating thickness often is expressed in micrometers; 25.4 micrometers = 1 mil. (2) A stationary or hand-held instrument used to measure thickness of free (unattached) films. [PCG] MIL. One thousandth (0.001) of an inch. 1 mil = 25.4 micrometers. Coating thickness is often expressed in mils or in micrometers. [PCG] Mil Profile. See Surface Profile. Mill Coating. Shop coating. Mill Scale. The heavy, bluish oxide layer formed during hot fabrication or heat treatment of steel and other metals. [PCG]
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PCI Study Guide- October 2007 Mineral Abrasive. Blast cleaning abrasive made from naturally occurring minerals, such as silica sand, olivine, staurolite, flint, garnet, zirconium, novaculite. Mineral Spirits. A petroleum-derived solvent used for thinning paint. Odorless mineral spirits have been refined to remove some odorous constituents. [PCG] Mist Coat. Also called a fog coat, a thin layer applied in a spray mist and used as a tack or adhesive coat. [PCG] Mixing Ratio. The ratio, usually by volume, of mixed components for a thermosetting coating specified by the manufacturer for complete curing into the desired film. Moisture Meter. Instrument used for determining water (moisture) content of materials, such as wood or concrete, by measuring its conductivity. Monomer. The starting compound for a polymerization reaction. A monomer can link with itself or with other monomers to form a polymer. [PCG] Monolithic. Material of uniform composition applied as a continuous surface or structure. [ASTM] Monolithic concrete is concrete cast with no joints other than construction joints. [ACI] MSDS. See Material Safety Data Sheet. Mud Cracking. A paint failure that looks like cracked mud. It normally is caused from shrinkage of excessive thicknesses of coatings during curing. [PCG] Muriatic Acid. An industrial form of hydrochloric acid used to clean concrete and masonry. [PCG] NDT. See Non-Destructive Testing. Near-White Blast Cleaning. According to SSPC-SP 10/NACE No. 2, Near-White Blast Cleaning, a near-white blast cleaned surface is free of all visible oil, grease, dirt, dust, mill scale, rust, paint, oxides, corrosion products, and other foreign matter and staining is limited to no more than 5% of each unit area of surface. [PCG] Needle Gun. A power impact tool with a bundle of steel needles with chiseled ends mounted in front of a piston that strikes them several times per second and pushes them against the surface being cleaned. Needle guns work best at removing loose or brittle material. Because each needle hits the surface individually, needle guns are useful for cleaning irregular surfaces, such as corners and crevices, or around bolt and rivet heads. [PCG] NIST Standard Thickness Plates. Small, thin reference squares of 1010 steel covered with different thicknesses of a non-magnetic metal (copper-chromium alloy with a nickel finish); used to calibrate magnetic dry film thickness gauges; made by the National Institute of Standards and Technology (NIST). Non-Conductive. A surface or material that will not conduct electricity. Non-Contact Thermometer. An instrument that determines surface temperature by measuring the amount of energy the surface emits. Non-Convertible Coating. Film-former which, after being deposited from a solution, dries to give a film that is unchanged chemically from its original composition and can be redissolved in a solvent from which it was originally deposited. See Thermoplastic. [CED] Nondestructive Testing (NDT). Determining physical or chemical properties without damaging item being investigated. Non-Ferrous. Not containing iron; pertaining to metals other than iron.
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PCI Study Guide- October 2007 Nonvolatile Matter (NVM). Of a coating, the solid material remaining after the volatiles (solvent) have been driven from the film under specified test conditions. The total percentage volatile present is obtained by subtracting the nonvolatile content from 100. Nonvolatile Vehicle. The coating binder dissolved or dispersed in the solvent (volatile vehicle) that remains to form a film after solvent evaporation. Non-Woven Abrasive Pad. A web of nylon fibers embedded with abrasive material in different sizes and densities. These pads can be used to remove dried soil, debris, and loose paint from many different surfaces, as well as loose rust and loose mill scale from steel. They can also be used to feather, or blend the edges of a repair area, with the surrounding surface. [PCG] Notch Gauge. See Wet Film Thickness Gauge, Notch Type. Novolac. Class of resins produced by the chemical reaction of phenol and formaldehyde; often used in high performance phenolic or epoxy coatings. See Bisphenol F. Nozzle Orifice Gauge. A tapered metal rod that can be inserted into the rear of a blast cleaning nozzle to determine the size of its orifice. The nozzle normally is replaced when the orifice size increases by 1/16 inch (1.6 mm). [PCG] Nuclide. A species of atom characterized by the constitution of its nucleus and hence by the number of protons, the number of neutrons, and the energy content.
O Offshore Platform. A stationary steel structure in an ocean or bay that is used by oil and gas industry operators for drilling or other production activities. Oil Canning. Bowing edges of a steel plate caused by thermal expansion and contraction. Oil canning can lead to a coating cracking at the edges. Opacity. The degree to which a material obscures a substrate, as opposed to the transparency, which is the degree to which a material does not obscure a substrate. [CED] Open Blast Cleaning. See Air Abrasive Blast Cleaning. Operating Mix. See Abrasive Mix. Orange Peel. A coating film defect with the textured look of an orange peel. [PCG] Organic Solvent. Liquid organic material including diluents and thinners that is used as a dissolver, viscosity reducer, or cleaning agent. Organotin. Tin compounds used in anti-fouling paints and wood preservatives. Their use is currently curtailed because of toxicity concerns. Osmotic Blistering. The raised areas (blisters) containing water that form on coating films when water diffuses through the film to dissolve underlying solvents or salts. The diffusion is caused by a difference in pressure or concentration between the metal-coating interface and the exposed film. Overblast. Areas where abrasive blasting has impinged on surfaces that were not intended to be blasted. Overspray. (1) Atomized coating particles that deflect from or miss the surface being sprayed. (2) Spray particles that are not wet enough to fuse when they reach the surface being sprayed. As a result, overspray may contaminate property beyond the surface being sprayed. [PCG] Oxidation. (1) In coatings, the introduction of oxygen into a molecule, thereby producing a cured film. [Paint/Coatings dictionary] Alkyds and drying oil-based coatings cure by
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PCI Study Guide- October 2007 oxidation. Oxidation during weathering can also destroy a film. (2) Metal corrosion and degradation of other substances caused or accelerated by oxygen in the air. [PCG] Oxygen Deficiency. Low oxygen in the atmosphere, generally below 19.5%, is a health hazard. Oxygenated Solvent. An organic solvent containing oxygen as part of its molecular structure. Alcohols, esters, and ketones are oxygenated compounds often used as coating solvents. [EPA, PCG]
P Paint Thermometer. Instrument designed for measuring the temperature of liquid coating materials by immersion. Parts Per Million (PPM). Measure of proportional content (e.g., of small amounts of contamination). PEL. See Permissible Exposure Limit. Pencil Testing. See Hardness Testing, Pencil Method. Pencil-Type Pull-Off Gauge. A pencil-shaped magnetic pull-off gauge for determining dry film thickness. See Magnetic Gauge. Percent Solids. See Non-Volatile Matter. Permissible Exposure Limit (PEL). The amount of a toxic material or harmful substance to which a worker may be exposed under OSHA regulations. If OSHA has established a PEL for a substance, by regulation the exposure must be kept at or below that level. PELs are expressed as parts per million (ppm) or as micrograms per cubic meter (µg/m3) and typically are based on time-weighted average concentrations for a normal 8-hour workday and a 40-hour work week. See also Threshold Limit Value. [PCG] Personal Protective Equipment (PPE). Devices worn to protect against hazards in the environment. Respirators, gloves, and ear protectors are examples. pH. The measure of the acidity or alkalinity of an aqueous solution. A pH of 7 represents neutrality, i.e., the solution is neither acid nor alkaline. pH values from 0 to 7 are acidic, the lower the pH value, the higher the degree of acidity; pH values from 7 to 14 represent alkalinity. The higher the pH value above 7, the greater the degree of alkalinity. [CED] Pigment. Finely ground, natural or synthetic, inorganic or organic insoluble particles that, when dispersed in a liquid vehicle provide color and other properties, including opacity, hardness, durability, and corrosion resistance to a coating. [IM] Pigment Volume Concentration (PVC). Ratio of the volume of pigment to the volume of total nonvolatile material (i.e., pigment and binder) present in a coating. The figure is usually expressed as a percentage. [CED] Pinhole. A holiday or discontinuity in a coating film approximately the size of a pin point, and extending entirely through the applied film, normally caused by solvent bubbling, moisture, or foreign particles. [PCG] Pinhole Detection. See Holiday Test. Pinpoint Rusting. Tiny, dispersed points of rust that can appear at pinholes and holidays in a coating. Very dense pinpoint rusting can appear on painted steel surfaces where the coating does not completely cover the blast cleaning profile. [PCG]
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PCI Study Guide- October 2007 Pitting. (1) Localized corrosion on a metal surface, confined to a point or small area, that takes the form of cavities. [ASM] (2) In concrete, pitting is localized disintegration, such as a popout. [ACI] Plasma Spraying. A spray application process in which metallic or thermoplastic powders are introduced into a plasma arc cavity that contains the gas stream of a plasma gun. After being melted, the powders are projected onto the surface being coated via the flow of the plasma jet. See also Flame Spraying, Metallizing, and Thermal Spraying. [PCG] Plasticizer. (1) A paint, varnish, or lacquer additive designed to soften and promote flexibility in the coating. [PCG] (2) A material that increases the plasticity of a fresh cement paste, mortar, or concrete. [ACI] Plural-Component Spraying. A coating application method that automatically proportions and mixes two or more components of a paint material in the process of delivering them to the spray gun. Plural-component spray equipment is used to apply coatings with a pot life that is too short to permit mixing and application by conventional air and airless spray equipment. [PCG] Pneumatic Adhesion Tensile Strength Testing Instrument (Patti). An instrument for determining the tensile adhesion of coatings to a surface, according to ASTM D 4541. This instrument is self-aligning, and consists of detachable loading fixtures having a flat, cylindrical base, a central grip for engaging the loading fixture, and a pressurized gas system for applying a continuous pull to the loading fixture. See Adhesion Test, Tensile (Pull-Off). Pneumatic Power Tool. Tool that is run by air pressure. Polymerization. Chemical reaction in which two or more small molecules (monomers) combine to form large molecules (polymers, macromolecules) that contain repeating structural units of the original molecules and have the same percentage composition as the small molecules if the small ones were of the same kind. [CED] Porosity. (1) Small interconnected voids, such as in concrete, which allow fluids to penetrate an otherwise impervious material. (2) The ratio, usually expressed as a percentage of the volume of voids in a material to the total volume of the material including the voids. [ACI] Pot Life. The time during which a coating material can be successfully applied to a substrate after the container is opened, or after catalysts, activators, hardeners, or other ingredients are added to initiate the curing reaction. Pot life often depends on temperature and/or humidity. [PCG] Powder Coating. (1) A 100% solids coating applied as a dry powder which, when baked at a sufficiently high temperature, melts out to form a continuous film. For thermosetting materials, a chemical reaction, either condensation or additional polymerization, also takes place. This fused film has the uniformity, color, toughness, and other properties generally associated with protective and decorative coatings. (2) A coatings application method that utilizes a solid binder and pigment. The solid binder melts upon heating and results in a pigmented coating upon cooling. [CED] Power Grinding. Abrading a metal or other hard surface with a motor-driven tool. Power Washing. The use of pressurized water (typically less than 5000 psi [34 MPa]) with or without chemical additives, detergents, etc., to remove contamination and debris from a surface. [PCG]
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PCI Study Guide- October 2007 Power Wire Brush. A power tool with a brush made of knotted or crimped wire bristles in the form of a wheel or a cup used to clean steel, concrete, or masonry surfaces. [PCG] PPE. See Personal Protective Equipment. PPM. See Parts Per Million. Pre-Job Conference. Meeting held before construction work is started to permit the contractor, owner, and other concerned parties to come to a common understanding of all work requirements. Primary Containment. (1) The main method of storing a product, e.g., a steel storage tank. (2) That portion of a nuclear power plant reactor building housing the nuclear reactor, a Class I area. Primer. First full layer of coating applied to a surface when a multicoat system is being used. Primers provide adhesion to a new substrate (wood, metal, masonry, or concrete), protect the substrate, and aid in the adhesion of additional coats of paint. The type and condition of the substrate and the painting system specified for a job affect the selection of the primer. Primers for steel work contain special anti-corrosive pigments. [PCG] Procurement Documents. Written records that describe the general terms and conditions of construction or other contracts. Profile Depth. A measure of surface roughness based on the distance between its peaks and valleys, sometimes expressed as an average. See Surface Profile. [PCG] Profile Depth Gauge. Gauge with instrumented probe for determining the profile height (depth) of abrasive blasted steel, as described in ASTM D 4417, Method B. Psychrometer. An instrument used to measure the wet and dry bulb temperatures of air. With the aid of psychrometric tables, these measurements can be used to determine the dew point and relative humidity of the air. [PCG] Psychrometric Tables. U.S. Weather Bureau Tables, originally published by the U.S. Department of Commerce, used to determine the relative humidity and dew point temperature from the dry and wet bulb readings obtained from the psychrometer. Pull-Off Adhesion Test. See Adhesion Test, Tensile (Pull-Off). Pull-Off Gauge. See Magnetic Pull-Off Gauge, Banana Gauge, and Pencil-Type PullOff Gauge. Pull-Off Strength. Force necessary to pull a bonded probe from a coated surface in a coating adhesion test. Pull Stub. Also called a dolly or loading fixture, the part of an adhesion testing apparatus that is affixed to the coated surface being tested. PVC. Pigment Volume Concentration; Polyvinyl Chloride.
Q Quality Assurance. The guarantee that the quality of a product is actually what is claimed on the basis of the quality control applied in creating that product. Quality assurance is not synonymous with quality control. Quality assurance is meant to protect against failures of quality control. [IUPAC, CED] Quality Control. The statement that a product specifically meets or exceeds some minimum standard based on known, testable criteria. [CED] Quantab Strip. Trade name for a commercial test strip used to determine the chloride content of an aqueous solution.
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PCI Study Guide- October 2007
R Reference Cell. Standard receptacle containing an electrode and electrolyte used as a point of reference for measuring electrical potentials; used in sacrificial anode and impressed current cathodic protection. Reflectance. The ability of a coating film to reflect or return the light that falls upon its surface. [PCG] Relative Humidity. The ratio of the actual pressure of existing water vapor to the maximum possible (saturation) pressure of water vapor in the atmosphere at the same temperature, expressed as a percentage. [ASTM, PCG] Release Agents. Materials used to prevent concrete from bonding to a surface. [ACI] See Form Release Agent. Replica Tape. A specially constructed tape used to measure surface profile. It is pressed against the surface to produce an impression of the profile; then, the impression in the tape is measured with a micrometer. The use of replica tape is described in ASTM D 4417 and NACE RP0287. Reservoir. Storage tank in which the diameter is greater than the height; the reverse is true for a standpipe. Resin. General term applied to a wide variety of more or less transparent and fusible products, which may be natural or synthetic. They vary widely in color. Higher molecular weight synthetic resins are more generally referred to as polymers. In a broad sense, this term is used to designate any polymer that is a basic binder material for coatings and plastics. [PCG] Respirator. (1) A device that supplies oxygen or a mixture of oxygen and carbon dioxide for breathing, used especially in artificial respiration. (2) A screenlike device worn over the mouth or nose or both to protect the respiratory tract. There are quite a variety of respirators, ranging from disposable dust masks to self-contained breathing apparatus. All have specific uses and limitations. [CED] Rigging. (1) The process of selecting and setting up supports, cables, and ropes, and scaffolding systems to provide safe access to an elevated work area. (2) The cables, ropes, and related equipment used with scaffolding. [PCG] Right-To-Know Legislation. See HAZCOM. Ring Extrusion Process. A method for extruding thermoplastic coatings onto pipe in which the die slit encircles the advancing pipe and the thermoplastic is extruded without seams as a plastic pipe over the steel pipe. Rotary Peener. A rotary impact power tool that uses rotating action to impact different shapes of heavy-duty steel cutters against a steel or concrete surface to remove heavy coatings and contaminants. Rotary peeners also can be used to grind concrete. [PCG] Rust Bloom. The first sign of rust on newly cleaned steel, indicated by slight surface discoloration. See Flash Rusting. [PCG] Rust Grade. In visual standards, the initial condition of unpainted steel before surface preparation. SSPC-Vis 1, a visual standard for steel surface preparation, outlines four rust grades: (1) Rust Grade A: the steel surface is completely covered with adherent mill scale; little or no rust is visible. (2) Rust Grade B: The steel surface is covered with both mill scale and rust. (3) Rust Grade C: The steel surface is completely covered with rust;
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PCI Study Guide- October 2007 little or no pitting is visible. (4) Rust Grade D: The steel surface is completely covered with rust; pitting is visible. [PCG]
S Sacrificial Protection. (1) The use of a metallic coating, such as galvanizing or zinc-rich paint, to protect steel. In the presence of an electrolyte, such as salt water, a galvanic cell is set up and the metallic coating corrodes instead of the steel. (2) The use of metal anodes that are slowly consumed to protect immersed or buried metals. See also Galvanic Corrosion and Galvanic Protection. [PCG] Sagging. (1) A coating surface irregularity caused by the downward flow of wet paint that produces an uneven film with a thick lower edge. [PCG] (2) Subsidence of shotcrete, plaster, or the like, due generally to excessive water in the mixture; also called sloughing. [ACI] Sag Resistance. The ability of a wet coating film to resist the downward flow that results in an uneven film with thick edges and runs. [PCG] Salt Spray Test. Test used to evaluate the resistance of coated metals or alloys to corrosion. It consists of a fine mist or fog of common salt (sodium chloride) solution sprayed on the surface. The test is described in ASTM B 117. [PCG] Sanding Disc. Flat, circular, powered implement used to abrade a surface. Saponification. Alkaline hydrolysis of fats, drying oils, or other esters whereby a soap is formed. A saponified coating may become sticky and discolored. In severe cases, the film may be completely liquefied by saponification. Loss of adhesion may occur as a saponified layer develops next to the substrate. [PCG] Scaffold. Equipment in variety of types, sizes, and rigging configurations used to support workers, materials, and equipment at elevated or otherwise inaccessible work sites. [PCG] Scaling Hammer. Impact tool used to remove corrosion products and other undesired materials from metal surfaces. Scratch Hardness. In determining coating hardness by pencil testing (ASTM D 3363), the scratch hardness is defined by the hardest pencil that will not scratch the film. See also Gouge Hardness. Scrub Resistance. The ability of a coating to resist being worn away or to maintain its original appearance when rubbed repeatedly with an abrasive material. Typically, the rubbing procedure can employ a brush, sponge, or cloth, wetted with an abrasive soap solution, in which case it is more accurately referred to as wet scrub resistance. [CED] Secondary Containment. A second or backup holding vessel surrounding a primary holding vessel. Under 40 CFR 264.193, the EPA lists requirements for lining secondary containment vessels so that they meet the standards for impermeability and for containing the liquid in the primary containment vessel should a leak or spill occur. [PCG] Sedimentation. Action or process of depositing matter (sediment) that settles to the bottom of a liquid (sediment).
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PCI Study Guide- October 2007 Self-Priming. A coating that can be used, perhaps in different consistencies, both to prime and to coat a surface. [PCG] Self-Curing. A coating that cures (crosslinks) without any special treatment after application. [PCG] Self-Leveling. The ability of a wet coating to form a uniformly flat or level surface. Sensitization. A state of immune-response reaction in which further exposure elicits an immune or allergic response. A person previously exposed to a certain material is more sensitive when further exposed to it. [CED] Shelf Life. The amount of time a coating or other material remains in usable condition during normal storage. [PCG] Shim. (1) A thin strip of non-magnetic plastic, metal, or other material of known uniform thickness used to calibrate coating dry film thickness gauges. (2) A strip of metal, wood, or other material employed to set base plates or structural members at the proper level for placement of grout, or to maintain the elongation in some post-tensioning anchorages. [ACI] Short-Term Exposure Limit (STEL). Maximum quantity or concentration of toxic material in a working environment for limited working times, usually 15 minutes. Shot Abrasive. Smooth, rounded abrasive normally made of steel. [PCG] Side-Extrusion Process. A method for extruding thermoplastic coatings onto pipe in which the coating is extruded from a straight slit in a die located beside the revolving and advancing pipe. The extruded coating forms a hot ribbon of plastic that flows onto the pipe surface as a spiral wrap, the edges of each ribbon melting into and fusing with the edge of the adjacent ribbon. Compare Ring Extrusion Process. Sieve Analysis. A procedure for determining the size distribution of a blast cleaning abrasive or other particulate matter based on the percentage of material that is retained on and passed through one or more standard screens. [PCG] Sieve Size. Size of an abrasive or other particulate matter determined from ability to pass through a series of different screens; the lowest screen size through which it will pass. Silica Sand Abrasive. A blast cleaning abrasive manufactured from material consisting predominantly of the mineral quartz, which is washed, dried, and screened (sieved). Exposure to breathable sizes of crystalline silica (10 micrometer [0.4 mil] or smaller) can cause silicosis, a progressive lung disease. [PCG] Silicate Resin. Inorganic polymer product with high temperature resistance based upon the hydrolysis of alkali silicates (e.g., potassium silicate) or alkyl silicates (e.g., ethyl silicate); used mostly for inorganic zinc-rich coatings. Silicosis. A chronic lung disease caused by the continued inhalation of silica dust. [CED] Skin Tanks. On ships, tanks constructed inside the hull for ballast, fuel oil, and void spaces. Some tanks are bounded by the side shell or bottom plating. The shell of the vessel is often referred to as its skin. The significance is that these tanks can contain hot oil or cold water. This influences the temperature of the steel of the outside surface. Skip Welds. Welds on metal components that are intermittent rather than continuous. Slag Abrasive. A blast cleaning abrasive made from slag produced by metal-smelting or coal-fired boilers and power plants. Most slags are processed by quenching in water, crushing when necessary, washing, and screening to produce an acceptable abrasive. Slag abrasive manufactured by an air-cooling process has a different mineral structure. The quality and durability of the abrasive depends upon the processing and can vary widely
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PCI Study Guide- October 2007 from batch to batch and from source to source. Typical slag abrasives include copper and nickel slag from metal smelting and coal slag from electric power generation. [PCG] Sling Psychrometer. A psychrometer with wet bulb and dry bulb thermometers and a swivel handle that allows the instrument to be whirled through the air to obtain constant wet and dry bulb temperature readings. These temperatures can be used with psychrometric tables to determine the relative humidity. See Psychrometer. [PCG] Slurry Blasting. Surface preparation method using pressurized air to propel an abrasive slurry. See Wet Abrasive Blast Cleaning. Solids By Volume (%). The volume of the nonvolatile portion of a composition divided by the total volume, expressed as a percent. Synonym: volume solids. [CED] Soluble Salt Contaminants. Water-soluble inorganic compounds (such as chlorides and sulfates) that contaminate a product. When soluble salts are present on a prepared steel surface, they may cause premature coating failure. Solvent. (1) Liquid, usually volatile, which is used in the manufacture of paint to dissolve or disperse the film-forming constituents, and which evaporates during drying and therefore does not become a part of the dried film. [CED] (2) Liquid used to dissolve and remove oil, dirt, grease, soil, and waxes from metal surfaces. [PCG] Solvent Cleaning. The use of organic solvents, detergents, alkaline cleaners, and steam cleaning to remove oil, grease, dirt, soil, and other, similar organic compounds from a surface. The specification SSPC-SP 1, Solvent Cleaning, is a consensus standard covering the procedures necessary for solvent cleaning of steel surfaces. [PCG] Solvent Resistance. The ability of a coating to resist solvent attack, solution, or disfigurement. See Solvent Rub Test. [CED] Solvent Rub Test. A practice for assessing the solvent resistance and/or cure of an organic coating that chemically changes during curing. ASTM D 4752 is the preferred solvent resistance test for ethyl silicate zinc-rich primer. [CED] Spark Tester. See Holiday Detector, High Voltage. Specification. A word that is used in several ways in the coatings industry. The term “job specification” refers to the written, legal document, usually part of a contract, that precisely describes an item of work that is to be accomplished. Many technical organizations prepare documents called specifications that describe products, procedures, or conditions. For example, SSPC’s Volume 2 includes many specifications covering surface preparation, abrasives, paints and paint systems, and paint application. Military, federal, state, and other agencies also have paint and related specifications. The Army and Navy also have documents called “guide specifications” (formerly called “type specifications”), which are called “engineering standards” by private industry. Specular Gloss. Reflection of light in one path, as from a mirror, as opposed to diffuse reflection in all directions. Spiral Wrap. The technique for applying a continuous ribbon or tape to a length of a pipe. The ribbon is positioned at an angle (less than 90 degrees) to the axis of the pipe such that each revolution of wrap results in one side of the ribbon being applied over the previous wrap and the other side being applied to the bare pipe surface. The amount of overlap is governed by the width of the ribbon and the angle the ribbon makes with the pipe. Compare to Cigarette Wrap. Spot-Blast. Localized high-pressure cleaning as used in surface preparation for maintenance painting.
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PCI Study Guide- October 2007 Spray Pattern. Shape of the area where atomized paint is deposited during air or airless spray application. [PCG] Squaring Up. A field term often used where production blasting and painting is conducted on a large area that will require several days for completion. An area (e.g., 1,000 ft.2) is chosen each day, using natural partitions as far as possible, that can be readily blasted, inspected, and primed (squared up) that day. The term may also be used to describe the application of topcoats on subsequent days according to a selected time schedule. Stainless Steel. Any of several steels containing 12 to 30% chromium as the principal alloying element; they usually exhibit passivity in aqueous environments. [ASM] Steel Abrasive. Cast steel shot or grit used for abrasive blast cleaning. Cast steel shot consists of nearly spherical particles of steel obtained by granulating a molten stream of metal with water or air, or by other methods. Cast steel grit consists of angular particles produced by crushing steel shot. [PCG] STEL. See Short Term Exposure Limit. Stitch Welding. See Skip Welding. Stress Corrosion Cracking. Cracking caused by corrosion together with the stresses in a metal. [PCG] Striping. Painting the edges of a surface or welds to give them extra protection. Striping is done before priming or before the application of a full coat of paint. [PCG] Superplasticizer. A (high-range) admixture capable of reducing water or flowability without causing undue set retardation or air entrainment in mortar or concrete. [ACI] Superstructure. (1) The part of the ship above the main deck. (2) The entire portion of a bridge structure that primarily receives and supports highway, railway, canal, or other traffic loads and in, its turn, transfers the resulting reactions to the bridge substructure. The superstructure may consist of beam, girder, truss, trestle or other types of construction. Surface Conditioner. Chemical material that prepares a surface to receive a coating or other material. Surface Preparation. Any method of treating a surface to prepare it for coating. Surface preparation methods include washing with water, detergent solution, or solvent; cleaning with hand or power tools; water washing or jetting with or without abrasive; or abrasive blast cleaning. SSPC and NACE International have a number of written and visual standards describing surface preparation prior to coating application. [PCG] Surface Profile. The contour of a blast-cleaned surface on a plane perpendicular to the surface. For steel, surface profile is the roughened surface that results from abrasive blast cleaning or power tool cleaning to bare metal, also call the anchor pattern. For wood and concrete, surface profile is simply the texture of the cleaned surface. Surface profile of steel is classified by its depth and its texture (rounded or angular). Surface profile depth is defined as the average peak-to-valley height of the roughness and typically ranges from less than 1 mil up to 5 mils (25 to 127 micrometers). See Profile Depth. Surface Profile Comparator. An instrument used to determine the profile of a blast cleaned surface by visual or tactile comparison of the surface with a series of reference surfaces of known profile depths. [PCG]
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PCI Study Guide- October 2007 Surfacer. Pigmented composition for filling minor irregularities to obtain a smooth, uniform surface preparatory to applying finish coats; usually applied over a primer and sandpapered for smoothness. [ASTM] Sweat-In Time. See Induction Time. Sweep Blast Cleaning. A fast pass of the abrasive blasting pattern over a surface to remove loose material and to roughen the surface sufficiently to successfully accept a coating. This method of cleaning is sometimes specified as SSPC-SP 7, Brush-off Blast Cleaning. See also Brush-Off Blast Cleaning. [PCG] Swing Scaffold. A scaffold with a platform or stage suspended from a structure by two ropes or cables so it can be raised or lowered as needed. The scaffold height can be adjusted either manually or with a hoist powered by electricity or compressed air. [PCG]
T Taber Abraser. An instrument used to measure abrasion resistance (ASTM D 4060). Specimen on a turntable rotates under a pair of weighted abrading wheels that produce abrasion through side slip. [CED] Tack-Free. Absence of tack or stickiness in an applied coating. A coating’s freedom from tack after suitable drying time. [PCG] Tagging. A means of protecting workers from injury or death caused by the accidental start-up or release of stored energy from equipment. It involves placing a tag on the power source as a warning not to restore energy to the piece of equipment. See also Lockout. Tape Test. See Adhesion Test, Crosscut. Tensile Adhesion Test. See Adhesion Test, Tensile (Pull-Off). Tensile Strength. The maximum tensile stress that a material is capable of sustaining. Tensile strength is calculated from the maximum load during a tension test carried to rupture and the original cross-sectional area of the specimen. [ASTM] Test Strip. Paper strip dipped into solution to estimate of amount of contaminant or other material present. Thermal Spray Coating (TSC). Solid coating materials melted before dispersion (spraying) on a surface. Thermal Spraying. A process for applying metallic wire, metallic powder, and thermoplastic powder. The material is melted and sprayed onto a surface to produce a uniform coating. Gas wire and electric arc guns are used for spraying metallic wire; plasma guns are used for spraying metallic and thermoplastic powders. See also Flame Spraying, Metallizing, and Plasma Spraying. [PCG] Thermit Reaction. Explosive effect that occurs when aluminum and iron oxide are heated. Aluminum pigmented paints associated with rusty steel are susceptible to the effect, leading to potential problems in hazardous environments such as gas, fuel oils, etc. Thermoplastic. A material that becomes soft when heated and hard when cooled without undergoing chemical change. While the material is soft, it can be reformed or molded. As used in the coatings industry today, the original meaning of the term thermoplastic has changed somewhat. It is now used to classify coating types according to how the resins cure, and the solubility of the cured film. The term thermoplastic is virtually synonymous with the term non-convertible. See Non-Convertible Coating. [PCG]
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PCI Study Guide- October 2007 Thermoplastic Powder. Powdered organic polymeric materials that are melted by heat; some are sprayed through a flame to melt them, applied to a substrate as a liquid, and then solidified on cooling to form a protective film without undergoing chemical change. Thermosetting. A material that permanently sets when subjected to heat, catalysts, ultraviolet light, or chemical reaction, and cannot be softened and reformed by reheating. As used in the coatings industry today, the original meaning of the term thermosetting has changed somewhat. It is now used to classify coating types according to how the resins cure, and the solubility of the cured film. Thus, the term thermosetting is virtually synonymous with the term convertible. See Convertible Coating. [PCG] Thinner. (1) The portion of a paint, varnish, lacquer, or printing ink, or related product that volatilizes during the drying process. [ASTM] (2) Any volatile liquid used for reducing the viscosity of coating compositions or components; it may consist of a simple solvent or diluent or a mixture of solvents and diluents. [CED] Thixotropic. Having a gel consistency that becomes liquid when stirred or brushed to permit application but returning to its original consistency upon standing. Thixotropic coatings are less likely to drip from a brush than other types and can be applied in rather thicker films without running or sagging. [V1] Threshold Limit Value (TLV). The TLV is the concentration of chemical substances in the air that workers may be exposed to daily without adverse effect. TLVs are recommended exposure limits and are not required by law to be met. [PCG] Tie-Coat. A paint specifically formulated to provide a transition from a primer or undercoat to a finish coat. Tie-coats may be used to seal the surface of a zinc-rich primer, to bond generically different types of coatings, or to improve the adhesion of a succeeding coating. [PCG] Tie Rod. A mechanical connection in tension used to prevent concrete forms from spreading due to the fluid pressure of fresh unhardened concrete. Also called a form tie. [ACI] Time Weighted Average (TWA). Maximum allowed exposure to toxic materials over a working period, usually 8 hours. Tin. A soft, silvery-white metallic element. Organotin compounds, once widely used in anti-fouling coatings, have been widely restricted because toxic tin compounds were picked up by marine organisms and got into their food chain. Titanium Dioxide TiO2. A high-opacity, bright white pigment, used as a prime pigment in paints, rubber, plastics. [CED] Titration. In chemical analysis, determining the reactive capacity, usually of a solution, especially, the analytical process of successively adding measured amounts of a reagent (as a standard solution) to a known volume or weight of a sample or sample solution until a desired end point is reached. [ASTM] Tolerance. The total range of variation (usually bilateral) permitted for a size, position, or other required quantity; the upper and lower limits between which a dimension must be held. [ASTM, CED] Toluene. An aromatic solvent used in paint manufacturing and as a thinner and cleanup solvent. The flash point of toluene is about 30˚F (-1˚C). [PCG] Tooke Gauge. See Destructive Dry Film Thickness Gauge. Top Coat. The last coating material applied in a coating system, specifically formulated for aesthetic and/or environmental resistance. Also referred to as the finish coat. [PCG]
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PCI Study Guide- October 2007 Topside. The area on the sides of the ship’s hull that are above the deep load line. Topside usually refers to the area from the deep load line to the rail (above the boottop). Sometimes the word encompasses the decks and areas above deck, such as hatches, masts, pipes, etc. These areas are exposed to the weather as opposed to immersion in the sea. Total Solids. See Nonvolatile Matter. Toxicity. The capacity of a substance to injure by chemical means. [PCG] Turbidity. Term used to indicate the degree of water sample cloudiness, which is caused primarily by the presence of colloidal matter. [IUPAC, CED] Type 1 Magnetic Pull-Off Gauge. See Magnetic Pull-Off Gauge, Type 1. Type 2 Magnetic Fixed Probe Gauge. See Magnetic Fixed Probe Gauge, Type 2.
U Ultrasonic Gauge. Instrument for measuring material thickness by the time sound takes to travel through it. Ultrasonic Thickness Measurement. Determining thickness of a solid substrate, such as steel, through equipment that applies wave energy above the normal hearing range and then times its retroreflection. Ultraviolet (UV). A band of electromagnetic radiation between 10 and 400 nanometers in wavelength. The part of the UV spectrum in the actinic region (280 to 315 nanometers) is especially destructive to paint films. Ultraviolet energy also sometimes is used to cure a coating. “Black light” is a popular term for UV radiation. [PCG] Undercutting. The penetration of a coating and the spread of delamination or corrosion from a break or pinhole in the film or from unprotected edges. [PCG] Upper Explosive Limit (UEL). The concentration at ordinary ambient temperatures of a compound in air above which an explosion will not occur if the mixture is ignited. UEL is expressed as a percent of the gas vapor in air by volume. When concentrations of a substance in air are below the upper explosive limit and above the lower explosive limit (LEL), the mixture will burn and explode. See also Lower Explosive Limit. [PCG]
V Vacuum Blasting. Abrasive blast cleaning using a vacuum shroud to capture dust, debris, and other materials while they are being generated and prevent them from escaping into the environment. See Abrasive Blast Cleaning. [PCG] Vehicle. The liquid portion of paint, in which the pigment is dispersed; it is composed of binder and thinner. [CED] Viscometer. An instrument for measuring flow properties. [CED] Viscosity. The quality or property of a fluid (i.e., paint) that causes it to resist flow. A high viscosity coating is thick; a low viscosity coating is thin. [PCG] Viscosity Cup. A laboratory or field instrument for measuring the viscosity of a liquid by timing the liquid’s flow through an opening in the bottom of a small bowl. Visual Comparator. One of several systems used to visually estimate the profile of an abrasive blasted steel surface. See Surface Profile Comparator. VOC-Compliant. Conforming to VOC regulations. See Volatile Organic Compound. B-32
PCI Study Guide- October 2007 Volatile. (1) Easily evaporated. (2) Any liquid that evaporates quickly. [PCG] Volatile Organic Compound (VOC). (1) Any organic compound that reacts in the atmosphere with nitrogen oxides in the presence of heat and sunlight to form ozone. (2) Any organic compound (other than those designated by EPA as having negligible photochemical reactivity) that is emitted into the atmosphere during the application or curing of a coating. It is detected by reference methods such as EPA Method 24 or ASTM D 2369. [PCG]
W Washability. Ease with which the dirt can be removed from a paint surface by washing; also refers to the ability of the coating to withstand washing without removal or substantial damage. [CED] Wash Primer. A carefully balanced one- or two-component system containing an inhibiting chromate pigment, phosphoric acid, and a synthetic resin binder mixed in an alcohol. On clean, light alloy or ferrous surfaces, and on many nonferrous surfaces, such primers provide excellent adhesion, partly due to a chemical reaction with the substrate, and a corrosion-inhibiting film that is a good basis for the application of subsequent coats of paint. [CED] Water Blast Cleaning. A water cleaning method in which abrasive is injected into the water stream. Waterborne Coatings. Paint, the vehicle of which is a water emulsion, water dispersion, or ingredients that react chemically with water. Also called water-based and waterreducible coatings. Water Break. The appearance of a discontinuous film (beads) of water on a surface, signifying nonuniform wetting and usually associated with a surface contamination. [ASTM, CED] Water Cleaning. A method of using pressurized water, heated or unheated, with or without detergent, to prepare surfaces for coating. Low-pressure water cleaning uses pressures up to about 34 MPa (5,000 psi); high-pressure water cleaning ranges from 34 MPa (5,000 psi) to 170 MPa (25,000 psi); and ultrahigh-pressure water cleaning uses pressures above 170 MPa (25,000 psi). When pressures exceed 69 MPa (10,000 psi), a jet nozzle is used and the process is called waterjetting. Waterjetting. The use of water at high or ultrahigh pressure to prepare a surface for recoating. High pressure waterjetting is cleaning performed at pressures from 69 to 170 MPa (10,000 to 25,000 psi). Ultrahigh pressure waterjetting is cleaning performed at pressures above 170 MPa (25,000 psi). [SSPC-SP 12/NACE 5]. Water Trap. A structural feature in which liquid (such as rainwater) may accumulate from the environment. Weathering. Behavior of coating films when exposed to natural weather or accelerated weathering equipment, characterized by changes in color, texture, strength, chemical composition, or other properties. [CED] Weathering Topcoats. Exterior finishes designed to resist deterioration from ultraviolet light, rain, and other natural destructive elements in the atmosphere. Weld Spatter. Beads of metal produced during the welding process that adhere to the surface near the weld. [PCG]
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PCI Study Guide- October 2007 Wet Abrasive Blast Cleaning. Surface preparation method using conventional dry abrasive blasting equipment supplemented with modules to inject water into the abrasive stream. Ideally, the water encapsulates the abrasive particles with a thin film of moisture to suppress and contain the dust generated by the impact of the abrasive with the substrate. Wet Bulb Depression t – tw. The difference between the dry-bulb temperature and the wet-bulb temperature. [ASTM] Wet Bulb Temperature, tw. The temperature recorded on a wet bulb thermometer. See also Dry Bulb Temperature and Psychrometer. [PCG] Wet Bulb Thermometer. The thermometer on a sling or other psychrometer with a bulb covered by a wet cotton sock. See Psychrometer. Wet Film Thickness (WFT). Thickness of the liquid coating film immediately after application. [CED] Wet Film Thickness Gauge, Notch Type. Gauge with one or more faces cut in a series of notches that is used to determine coating wet film thickness as described in ASTM D 4414. Wetting. Ability of a vehicle to spread uniformly and rapidly over the surface of pigment particles. A vehicle with good wetting properties assists in the grinding or dispersion of pigments and the ability to wet the surface to which the finished coating is applied. [CED] (2) The ability of a coating to come into close contact with the surface over which it is applied. [PCG] Wetting Agent. Material used in a coating to reduce the surface tension of the vehicle or binder in order to assist in grinding or dispersing pigments or to improve the ability of the coating to wet the surface. [PCG] White Metal Blast Cleaning. Highest grade of blast cleaning. According to SSPC-SP 5/NACE No. 1, a white metal blast cleaned surface is free of all visible oil, grease, dirt, dust, mill scale, rust, paint, oxides, corrosion products, and other foreign matter. [PCG] Wire Brush Cleaning. Cleaning a surface with a hand or power tool wire brush. [PCG] Work Mix. See Abrasive Mix. Work Permit. Formal instruction, issued daily or weekly, to allow work to take place in a hazardous environment. Woven Roving. A cloth consisting of glass fibers woven in a pattern to impart strength when used to reinforce a coating or other composite system.
X Xylene. An aromatic solvent used in the manufacture of paints. It also is used widely as a thinner and cleanup solvent. The flash point of xylene is about 80°F (27°C). [PCG]
Z Zinc. A hard, metallic element with a bluish tinge. Zinc or its compounds are used as reinforcing and corrosion-resistant pigments. Zinc dust is used in zinc-rich coatings to provide galvanic protection to steel. It is also the basis for galvanizing and sprayed zinc coatings.
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PCI Study Guide- October 2007 Zinc-Rich. High in zinc dust content; a generic type of coating described in SSPC Paint 20. Zinc-Rich Coating. Anti-corrosive coating for iron and steel. Zinc-rich coatings use zinc dust in a concentration sufficient to provide electrical conductivity in the dried film. This enables the zinc metal to corrode preferentially to the ferrous substrate, giving galvanic protection. [PCG] See also Galvanic Protection.
Bibliography ACI: Cement and Concrete Terminology. ACI International: Farmington Hills, MI, 2000. ASM Metals Handbook. ASM International: Metals Park, OH, 1987. ASTM Annual Book of Standards. ASTM: West Conshohocken, PA, 2003. Bridge Inspector’s Training Manual/90. U.S. Department of Transportation/Federal Highway Administration: Washington, DC, 1979. Coatings Encyclopedic Dictionary (CED). Stanley LeSota, ed., Federation of Societies for Coatings Technology: Blue Bell, PA, 1995. Dictionary of Architecture and Construction (DAC). C.M. Harris, ed., McGraw-Hill: New York, 1975. EPA: Glossary for Air Pollution of Industrial Coatings Operation. U.S. Environmental Protection Agency: Washington, DC, 1983. Industrial Lead Paint Removal Handbook (ILPR). Kenneth A. Trimber, ed., SSPC: Pittsburgh. IUPAC Glossary of Atmospheric Chemistry Terms. Atmospheric Chemistry Division, National Center for Atmospheric Research: Boulder, CO, 1990. MPDA: The Master Painter’s Painting and Decorating Terminology Glossary. Master Painters & Decorators Association: Burnaby, B.C., 1997. PDC: Painting and Decorating Craftman’s Manual and Textbook. Painting and Decorating Contractors of America: Fairfax, VA, 1975. Protective Coatings Glossary. SSPC: Pittsburgh, 2000.
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PCI Study Guide- October 2007 Appendix C
Arithmetic
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