Application of the K2 asbestos screening test in Colorado schools.
Baldwin-CA; Beaulieu-HJ; Buchan-RM
Am Ind Hyg Assoc J 1982 Aug; 43(8):602-604
The possibility of school personnel utilizing the NIOSH K2 asbestos screening test in school districts conducting asbestos (1332214) detection programs was investigated. It is stated that a simple, reliable, and safe procedure for asbestos detection might allow school districts to reduce analytical costs by conducting initial tests themselves. The authors used the K2 asbestos screening test to analyze 185 samples of material suspected of containing asbestos collected from Colorado public schools. Samples collected included materials from ceiling tiles, sprayed surfaces, pipe lagging, and jackets on furnaces and boilers. Samples testing positively in the K2 test were secondarily analyzed using polarized light microscopy to confirm the presence of asbestos. The K2 test results indicated that 160 of the 185 samples tested contained asbestos. Of these, 113 gave a positive reaction to the magnesium test for chrysotile (12001295) and 75 (66 percent) of these magnesium positive samples were shown by polarized light microscopy to actually contain asbestos. All but five of these positive samples contained chrysotile. The iron test for crocidolite (12001284) or amosite (12172735) was positive in 47 samples, 19 (40 percent) of which were actually true positives. Of these 19, 11 contained only chrysotile, indicating false negative magnesium tests. The authors conclude that, due to the difficulties inherent in interpretation of color reactions in the K2 test, the hazardous nature of the reagents used, and the lack of precision in the hands of untrained personnel working in the field, the K2 test cannot be recommended for use by school district personnel. It is suggested that bulk samples collected from schools should be sent directly to a laboratory experienced in identifying asbestos by polarized light microscopy or a similarly acceptable technique.
NIOSH-Publication; NIOSH-Grant; Microscopic-analysis; Asbestos-fibers; Screening-methods; Colorimetry; Air-quality; Respirable-dust; Laboratory-testing
1332-21-4; 12001-29-5; 12001-28-4; 12172-73-5
American Industrial Hygiene Association Journal
Inst of Rural Environ Health Colorado State University 110 Vet Science Building Fort Collins, Colo 80523