Controls of Fugitive Emissions of Residual Ethylene Oxide inCommercial Medical-supply Sterilization

Residual ethylene oxide (EO) off-gassed from sterilized products is the main source of worker exposures in medical-supply sterilization. Three engineering designs that potentially reduce exposures were proposed, and their effectiveness was determined via exposure monitoring. Installation of additional venting ducts on the sterilizer significantly improves venting function and reduces worker short-term (~15 min.) exposure during un-loading sterilized goods. Similarly, application of a canopy-type exhaust hood, with baffles to minimize air shortcut, near the sterilizer door to vent the newly sterilized goods also reduces short-term exposure. Lastly, establishment of enclosed and venting systems for product aeration was effective in controlling fugitive run-away of EO during aeration/storage, and reducing air concentrations in the relevant areas. The improvements were significant and met the permissible exposure limits.