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COATINGSPRO JANUARY 2017 29 Testing, Testing It's up to the inspector to complete a variety of tests on a coatings jobsite for non-visible contamination. ese may include the Bresle Patch test, conduc- tivity testing, chloride testing, and ferrous iron testing. Each of these tests come with potential hazards. When testing for surface contam- inants, inspectors often use the Bresle Patch, which tests for salts (and pH in residual soil). is test is not difficult to use, but it does present a hazard for the inspector: It uses a hypodermic needle that can cause puncture wounds. Use this test carefully, and pay close atten- tion to the process. Becoming distracted during the testing process could lead to infection or a communicable disease. Electronic conductivity test equipment is used in conjunction with the Bresle Patch. It, too, is not always intrinsically safe, and a battery spark could lead to fire or explosion in a solvent-rich environment. ere are safe models available, but the cost is much greater. e cost versus benefit is job-size specific; the larger projects may justify the additional cost. T he sleeve test and K itagawa tube is a simple test for detection of chlorides. During the process of the test, breaking glass tips off both ends of the K itagawa tube presents an opportunity for the small glass pieces to injure eyes. T he larger portion of the tube also has an irregular and shar p surface that could cause a cut or puncture wound. Wearing both gog gles and gloves are a good safety precaution when using this test. Testing for ferrous ions is extremely easy, but it also requires caution. e test uses an absorbent patch treated with a chemical that detects the presence of ferrous ions. e chemical (5 percent potassium ferricyanide) may induce diarrhea if ingested. Precautionary measures, such as wearing rubber gloves, are always necessary. Inspectors may also need to complete tests for visible contamina- tion. e water break test for residual oil is simple and often used when there is too much natural light for ultraviolet (UV) equipment to identify residue. However, water can cause the surface to become slick. If the test is performed at freezing temperatures, ice can also make the surface hazardous. e inspector may want to consider using a black (UV) light to test for residual oil instead. However, the light puts out a beam of 350 NM, a wavelength that can cause serious eye injury or blindness. e UV unit requires the use of a filtering eyewear. As an additional precaution, never look directly into the light source. Surface Preparation Inspectors are often on the jobsite throughout the coatings process — from the initial testing through the surface preparation and into the final test of the coating thickness. During the surface preparation process, in particular, there can be a variety of hazards that the inspector needs to be aware of and be protected from. • SSPC Surface Preparation (SP) 2/ International Organization for Standardization (ISO) 8501-2 (aka St2 or St3): Hand Tool Cleaning. Hand tool cleaning instruments are seemingly easy to handle and not thought to be dangerous. However, they do warrant attention. One frequently used tool is a dull putty knife, which is used to verify accep- tance under different standards. Scraping steel on metal surfaces can potentially create sparks that can be dangerous in a solvent-rich environ- ment. Also, brass hand tools are not as tough as steel and are more easily breakable during cleaning; such Inspector's Corner Environmentally Safe VpCI ® /MCI ® Technologies EXCELLENCE Q U A I T Y ® C O R P O R AT I O N PRODUCTIVITY INVESTMENT AND COST REDUCTION Wr i te in Re ad e r In q u ir y #291