Trends in U.S. Chemical Industry Accidents

This paper presents the results of an analysis of the accident history data reported under Section 112(r) of the Clean Air Act Amendments. This data provides a fairly complete record of the consequences of reportable accidental releases occurring during the time frame 1995-1999 in the U. S. chemical industry and covering 77 toxic and 63 flammable substances subject to the provisions of 112(r). Our analysis shows that the frequencies of reported accidents climbed from approximately one per 67 facilities in 1994 to one in 35 facilities in 1997 and 1998, then declined again to approximately one per sixty facilities in 2000. While this change was highly statistically significant (p<.0001), some or all of this trend may be due to spurious data collection effects. No statistically significant differences in injury rates over time were observed. Future rounds of RMP*Info reporting may allow trend analyses under weaker assumptions than required here.