OUR RECOMMENDATIONS:
1) Complete a full review and generate an up to date description of sterilization operations, including current inventory of sterilization, emission control, and fugitive emission management equipment, as well as a current quantification of annual EtO usage, and a complete description of how product is handled through the sterilization, product transfer (if applicable), aeration, and post-aeration processes.
2) Perform testing to quantify actual fugitive emissions through interior ambient monitoring and source emissions measurement at fugitive emission management discharge points. Potential fugitive emissions sources include: sterilant gas storage/handling areas, sterilant gas supply load stations and associated plumbing, sterilizers and their associated plumbing and access openings, vacuum pumps and other chamber evacuation systems, product transfer areas, sterilized product post-process storage areas, as well as fume hoods, ducting, and exhaust systems designed to ventilate these associated areas. USEPA is proposing the use of an emission factor of 0.5-1.0 percent of EtO usage for the calculation of fugitive emissions from this source category, and will be soliciting comments as part of their upcoming information request commercial EtO sterilization facilities. In order to offer any acceptable alternative(s) to this assigned emission factor, the USEPA is requesting that facilities provide documentation (test data, emissions testing results, calculations, etc.) to substantiate any deviations. Your fugitive emissions may be substantially less than EPA estimates, which will otherwise be arbitrarily applied to your facility for use in determination of permit conditions, emission control requirements, and permit/emissions fees.
3) Conduct a comprehensive evaluation and/or demonstration of compliance with regulatory requirements for emission control and emissions, with an accurate quantification of total stack emissions. This testing should be performed under both best-case process and emission-control conditions (i.e. with new or recently replaced catalyst or adsorbent media, and under process conditions most conducive to optimal demonstration of compliance), and also under normal process and emission-control conditions (diagnostic purposes only, informational testing to evaluate emission control performance prior to servicing of emission-control equipment, under normal process loading).
4) Measure exterior ambient/fence line EtO concentrations during sterilization operations, for use in environmental impact modeling, which should be performed with actual rather than theoretical EtO concentration and emissions data.
5) Evaluate/test potential wastewater EtO emissions. USEPA is also investigating the significance of potential waterborne EtO emissions. The possibility of wastewater EtO emissions exists whenever water that has been directly exposed to EtO is discharged to the public owned treatment works (POTW), i.e. down the drain. The most common such interaction occurs in liquid ring vacuum pumps, either water or oil sealed, where water is discharged continuously, or accumulated in an oil/water separator tank and discharged periodically. Any other source of water or collected condensate which contacts EtO and is ultimately discharged to the POTW also qualifies.
