PROPOSITION FOR A METHOD OF EVALUATING THE WORK ENVIRONMENT WITH REGARD TO AIR-BORNE TOXIC SUBSTANCES

Abstract

In order to prevent workers from occupational exposure to toxic air-borne sub-stances, a method for deciding the acceptability of the work environment is pro-posed. The condition of the work environment is expressed as a function of both the geometric mean and geometric standard deviation of the general air concentra-tions of the hazardous substance in the work environment. This method permits a classification of the condition of the work environment into three control zones with the help of two control levels which are derived from the exposure limit values. In order to check the validity of this method, the exposure concentrations of 118 workers in 29 unit workplaces to various hazardous substances were examined. When the condition of the work environment fell below the first control level, the probability that the concentration to which the workers were exposed exceeded the exposure limit value was less than several percent. When the condition of the work environment exceeded the second control level, the probability was more than 50%.