A Statistical Evaluation of Asbestos Air Concentrations

Abstract

Both area and personal air samples collected during an asbestos abatement project were matched and statisti cally analysed. Among the many parameters studied were fibre concentrations and their variability. Mean values for area and personal samples were 0.005 and 0.024 f.cm -3 of air, respectively. Summary values for area and personal samples suggest that exposures are low with no single exposure value exceeding the current OSHA TWA value of 0.1 f.cm-3 of air. Within- and between-worker analysis suggests that these data are homogeneous. Comparison of within- and between- worker values suggests that the exposure source and variability for abatement are more related to the process than individual practices. This supports the importance of control measures for abatement. Study results also suggest that area and personal samples are not statisti cally related, that is, there is no association observed for these two sampling methods when data are analysed by correlation or regression analysis. Personal samples were statistically higher in concentration than area sam ples. Area sampling cannot be used as a surrogate expo sure index for asbestos abatement workers.