Field Evaluation of a Novel Exposure Assessment Strategy Using Respirable Coal Dust Exposures During Heat Plant Coal Receiving Operations

An exposure assessment strategy (EAS) determines the number of samples required to characterize an occupational health exposure's acceptability. A novel EAS (AFIT-EAS) was developed with the objective of maximizing the sensitivity for detecting unacceptable exposures, while minimizing the total number of samples needed. The purpose of this field evaluation was to use data from a comprehensive sampling campaign (SC) to compare the AFIT-EAS with two commonly used EASs: the Occupational Safety and Health Administration's (OSHA-EAS) and the American Industrial Hygiene Association's (AIHA-EAS). 10 randomly sampled replicates were selected from the SC. The number of samples selected per replicate was in accordance with each respective EAS's protocol. Results show that the true health risk assessment for the SC was evaluated as unacceptable; therefore, EAS conclusions matching this result were counted as successful. The OSHA-EAS of one (1) sample per replicate was the least successful with a maximum success rate of 20%. The AIHA-EAS of six (6) samples per replicate was equal to the AFIT-EAS of three (3) samples per replicate with a maximum success rate of 100%. The AFIT-EAS was found to be more accurate than the OSHA-EAS and equally accurate as the AIHA-EAS, while using only half as many samples.