Abstract
Occupational exposures to potentially hazardous agents may vary considerably because of worker mobility, or workplace contaminant levels that fluctuate within or between-days. In addition, individual susceptibility to adverse health effects varies among identically exposed workers. Therefore, accounting for these variables can be difficult during assessment of worker exposure for occupational health and OSHA compliance purposes. This is particularly true when there is varied and repeated exposure from day to day. A cost-effective monitoring strategy for evaluating repeated employee exposure and potential health risk that considers the foregoing exposure variables is desirable. The method this article proposes uses a well-planned sampling strategy featuring 4-hr, rather than the traditional 7 or 8-hr sampling durations. Use of 4-hr samples has been found to improve monitoring efficiency without significantly reducing sampling precision or accuracy. Statistical protocols applied during the sampling procedure and subsequent data analysis also combine to minimize the frequency and duration of samples required to reach a decision regarding the significance of a worker's exposure. The development of an Acceptable Risk Level (ARL) is another important element of the proposed method. An ARL is a variable based on risk assessment and risk management principles, which have been established by the employer for each contaminant. The ARL is dependent on the contaminant's toxicity and the time pattern and spacing of successive exposures. Ultimately, an ARL can be developed by an employer for the productive allocation of health and safety dollars to ensure worker protection.