Abstract
An assessment of the employee's exposures to industrial hazardous substances using the proposed method described earlier was conducted on 49 workers exposed to lead.
As it is assumed that the daily exposure averages are lognormally distributed, geometric standard deviation (σg) representing true interday fluctuations of the daily exposures was estimated by personal exposure measurements of every worker for two consecutive days. The estimates (Sg) ranged from 1.00 to 5.35 with a median of 1.4 and a 90% upper limit of 2.4.
According to a classification scheme in the proposed method, exposure levels (I to III) were calculated using σg of 1.4 and 2.4. An exposure class based on a single day measurement was evaluated and compared to that based on measurements for two consecutive days. As a result, the decision of the exposure levels and classes from only one day monitoring could be made by using both σg of 1.4 and 2.4, representing ordinary and high interday fluctuations, respectively.
More accurate estimate of geometric standard deviation of interday fluctuations by exposure monitorings would provide a more reliable assessment of the worker's long-term exposure situation.
