The effectiveness of U.S. OSHA process safety management inspection – A preliminary quantitative evaluation

This study attempted to evaluate the inspection effectiveness of the U.S. OSHA process safety management (PSM) standard using statistical correlation test. A total of 6578 citations of past 1277 OSHA PSM inspections from 1992 to 2006 were quantitatively compared with the findings of the U.S. Chemical Safety and Hazard Investigation Board (CSB) investigations on root and contributing causes of 19 major chemical accidents. Nonparametric Spearman's coefficient of rank correlation tests showed a moderately strong agreement between OSHA PSM inspection citations and CSB findings at p < .01 significant level, and the degree of agreement increased with time. These results suggested that past OSHA PSM inspections had cited the problems that were the accident root causes, and the effectiveness of PSM citations has been improved as more inspections were conducted since the standard promulgation. However, factors such as standard coverage, inspection frequency, inspection resources allocation, and inspection strategy, were critical for effective PSM standard enforcement and implementation. Future studies should include more aspects of PSM citations and CSB accident investigation data for better evaluation of inspection effectiveness. The results may be valuable to the PSM enforcement policy makers.