Exposure Models for the Prior Distribution in Bayesian Decision Analysis for Occupational Hygiene Decision Making

Abstract

This study introduces two semi-quantitative methods, Structured Subjective Assessment (SSA) and Control of Substances Hazardous to Health (COSHH) Essentials, in conjunction with two-dimensional Monte Carlo simulations for determining prior probabilities. Prior distribution using expert judgment was included for comparison. Practical applications of the proposed methods were demonstrated using personal exposure measurements of isoamyl acetate in an electronics manufacturing facility and of isopropanol in a printing shop. Applicability of these methods in real workplaces was discussed based on the advantages and disadvantages of each method. Although these methods could not be completely independent of expert judgments, this study demonstrated a methodological improvement in the estimation of the prior distribution for the Bayesian decision analysis tool. The proposed methods provide a logical basis for the decision process by considering determinants of worker exposure.

[Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplementary resource: Coding of the MC Simulation (SSA Method)]

Keywords:

• AIHA exposure rating scheme
• Bayesian decision analysis
• COSHH Essentials scheme
• prior decision distribution
• structured subjective assessment (SSA)
• two-dimensional (2-D) Monte Carlo simulation

ACKNOWLEDGMENTS

The authors are sincerely thankful to Dr. Gurumurthy Ramachandran (University of Minnesota) and Dr. Abbas Virji (NIOSH/Division of Respiratory Disease Studies) for reviewing this manuscript prior to journal submission. The authors also would like to thank Nicholas Dow Schnaufer and J. Mark Brooks who helped with the field survey and sample collection. This project was funded internally by the National Institute for Occupational Safety and Health (Project HELD 0004 -External validation of Tier 1 and Tier 2 models under REACH).

The findings and conclusions in this report are those of the author(s) and do not necessarily represent the official position of the Centers for Disease Control and Prevention. ACGIH TLVs are provided for information purposes only and should not be construed as implying endorsement.