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50 MARCH 2017 COATINGSPROMAG.COM remover at a 75:1 ratio. Specs called for fewer than 20 parts per million (ppm) for non-immersion and 5 ppm for immer- sion applications (pilings between mean low tide and mean high tide). A lpine ran tests beforehand using CHLOR*R ID'S CHLOR*TEST kits. As expected in that environment, untreated steel proved way too salty to paint. "Before waterjetting, the samples simply maxed out the test kit readings," said Ofsharick. "After waterjetting only, the levels fell to 30–40 ppm. With CHLOR*RID added, we brought it down to single digits in most cases, at times zero or not detectable. Slawomir Plokarz, a NACE Coating Inspector Program (CIP) Level 1 inspector on our staff, was on hand during the entire project to take readings and send in daily reports. Only very few times did we have to go back to get below specifications." Hosed! Before waterjetting, crew members donned Guardian safety harnesses and lanyards. ey then rigged containment netting around the deck perimeter to prevent loosened coatings from entering the ocean. e nozzle man geared up in a rain suit and 3M face shield, and he donned TurtleSkin gaiters and thick rubber gloves. Ofsharick explained that nozzle opera- tors wore thick gloves because the stream of water exiting the UHP machine at 40,000 psi (275.8 MPa) was hot: 150‒200° F (65.6‒93.3° C). Gloves and protective clothing helped prevent burns. Due to financial constraints, specs on this project called for surface prep to adhere to NACE WJ-4/Society for Protective Coatings (SSPC) Surface Preparation (SP) WJ-4: Waterjet Cleaning of Metals — Light Cleaning. at standard typically leaves intact coating in place, according to Ofsharick. e A lpine crew quickly discovered they could achieve an even higher level of surface prep by holding the nozzle a bit closer than normal — at less than 6 inches (15.2 cm). Hey, A lpine's not opposed to giving owners a better end product, as long as they don't get hosed in the process! "We took a good look at our UHP production rates and the extra coatings involved (in some areas, removing more exist- ing coatings required full prime instead of spot prime)," said Ofsharick. "We decided we could remove up to 80 or 90 percent of the coatings, hit our production numbers, and still be okay from a cost standpoint." e crew prepped the top deck section by section, and they wasted no time gearing up to apply two coats of Carboline's Carboguard 690. e phenalkamine epoxy exhibits outstand- ing moisture tolerance during application and can be used on structural steel, piping, and equipment exposed to marine environments, according to the Carboguard 690 product data sheet. W hile one crewman mixed the 4:1 product, others rigged up their Graco King 68:1 airless sprayer with a Graco 510 gun and #517 tip. e crew found that by holding the 510 gun about 12 to 14 inches (30.5‒35.6 cm) from the deck at a right angle, they were able to lay down a prime coat of Carboline Carboguard 690 at 6 to 10 mils (152.4‒254 microns) wet film thickness (WFT) in a single pass with maximum efficiency. e crew The top deck received Carboguard 690 at 6- 10 mils (152.4-254 microns) WFT and Carboguard 690 at 7-11 mils (177.8-279.4 microns) WFT. Pipes, valves, etc. were spot primed with Rustbond and then coated with Carbothane 133LH. Offshore Oil Crew Using underdeck netting, two coats of Carboguard 690 GF went down at 24-42 mils (609.6-1,066.8 microns) wet film thickness (WFT). Pilings were spot primed and coated Carbomastic 615 at 7-14 mils (177.8-355.6 microns) WFT. While using the waterjetting rig, the crew used water transported to the site with CHLOR*RID. The material was used to remove soluble salts, and after, CHLOR*TEST kits were used to test the salt levels.