Evaluating OSHA's ethylene oxide standard: Exposure determinants in Massachusetts hospitals

Objectives. This study sought to identify determinants of workplace exposures to ethylene oxide to assess the effect of the Occupational Safety and Health Administration's (OSHA's) 1984 ethylene oxide standard. Methods. An in-depth survey of all hospitals in Massachusetts that used ethylene oxide from 1990 through 1992 (96% participation, N=90) was conducted. Three types of exposure events were modeled with logistic regression: exceeding the 8-hour action level, exceeding the 15-minute excursion limit, and worker exposures during unmeasured accidental releases. Covariates were drawn from data representing an ecologic framework including direct and indirect potential exposure determinants. Results. After adjustment for frequencies of ethylene oxide use and exposure monitoring, a significant inverse relation was observed between exceeding the action level and the use of combined sterilizer-aerators, an engineering control technology developed after the passage of the OSHA standard. Conversely, the use of positive-pressure sterilizers that employ ethylene oxide gas mixtures was strongly related to both exceeding the excursion limit and the occurrence of accidental releases. Conclusions These findings provide evidence of a positive effect of OSHA's ethylene oxide standard and specific targets for future prevention and control efforts.