Asbestos fiber counts in work zone area of an asbestos-cement factory

Levels of asbestos fibers in air at work zone in asbestos-cement (AC) sheets manufacturing factory, M/s Sturdy Industries Ltd, Patiala, Punjab have been studied. Air samples were collected from fiber godown, ingredients mixing, AC sheet manufacturing and the main gate. Phase contrast and polarized microscopic observations on asbestos fibers collected on membrane filters suggests that they are chrysotile. A detailed analysis shows the prevalence of chrysotile fibers (0.04-0.07 f/cc) in the working environment. These fiber counts are less than the existing Indian Standard (0.5 f/cc) and proposed Indian Standard (0.1 f/cc)

Study of asbestos fibre levels in and around a brake-lining industry

437-439 In India, out of 673 small-scale and 13 large-scale asbestos-based industries, only 60% industries are in operation. The present report reveals the exposure of commercial asbestos (chrysotile) in the occupational as well as ambient air environment of the brake-lining industry using membrane filter method of Bureau of Indian Standards (BIS). The fibre concentrations in 9 samples collected in the occupational environment was 0.123-0.238 f/cc (mean 0.187 ± 0.03) and that in 6 samples from surrounding ambient air was 0.002-0.007 f/cc (mean 0.004 ± 0.00). All samples showed fibre concentration lower than the threshold limit values (TLVs) prescribed by BIS at 0.5 f/cc. Morphological analysis of samples further under phase contrast and polarized microscopy indicates the presence of chrysotile asbestos, which acts as carcinogen as well as co-carcinogen. </smarttagtype