DECONTAMINATION TESTING OF HIGHLY CONTAMINATED PROTECTIVE COATINGS

Decontaminability measurements of 34 protective coatings (primarily vinyls and epoxies) and 10 comparative control surfaces (metals, glass, and plastics) highly contaminated with either mixed fission products from typical Purex waste or Oak Ridge National Laboratory Thorex waste did not indicate any unusual improvement over coatings tested in 1950 (AECD-2296). These measurements and chemical rcsistance tests were made of the protective coatings in common acids, alkalis, and deionized water at 81 and 120 deg F as a guide in the selection of coatings for radiochemical plant applications and to determine if coatings containing water vehicles could be substituted for coatings containing more hazardous organic solvent vehicles. Vinyl base coatings were superior in both decontaminability and chemical resistance. The two watervehicle coatings evaluated were markedly inferior to organic-vehicle vinyls. A vinyl wallpaper'' was decontaminated poorly with the reagents used. Water and 3M HNO/sub 3/ removed Purex contaminants relatively efficiently but were relatively ineffective for the removal of Thorex contaminants. Coatings determined to be sufficiently decontaminated from Purex waste by a water flush and acid scrub and to be of superior resistance to common acids and alkalis are given. (auth