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Hazardous Air Pollutants: Ethylene Oxide

Ethylene Oxide - Updates

Update on EPA’s work to review the National Emissions Standards for Hazardous Air Pollutants (NESHAP) for Miscellaneous Organic Chemical Manufacturing and the NESHAP for Ethylene Oxide Commercial Sterilizers.

SEPTEMBER 13, 2019 Today, EPA is providing an update on the status of the Agency’s reviews of two National Emissions Standards for Hazardous Air Pollutants (NESHAP). EPA is reviewing the rules as part of its two-pronged approach the Agency is taking to address emissions of ethylene oxide in the U.S.

A draft proposal for the Miscellaneous Organic Chemical Manufacturing NESHAP is at the Office of Management and Budget for interagency review. EPA expects to issue that proposal for public review and comment as soon as interagency review is complete. The Agency is under a court order to take final action on the rule by March 13, 2020.

For the NESHAP for Ethylene Oxide Commercial Sterilizers, EPA has been working over the past year to compile information on control technology options and costs for the more than 100 sterilizers that the rule would potentially cover.  The Agency intends to take two actions in October to help obtain additional information EPA needs to ensure we have a solid data-based record to support our rulemaking. Those actions include:

  • Issuing an Advance Notice of Proposed Rulemaking (ANPR) that will outline the potential approaches that EPA could take in its upcoming rule, along with the technologies available for controlling ethylene oxide emissions. The ANPR includes an opportunity for public comment, along with an opportunity to provide EPA additional data and information to support the future rulemaking.
  • Issuing a request for information to several commercial sterilization companies under section 114 of the Clean Air Act. This will require companies to provide information that would support a proposed rulemaking, including data on specific facility characteristics, control devices, work practices, and costs associated with installation and operation of emission reduction measures.

Separately, because nearly one-third of the sterilizers potentially affected by the rule are small businesses, the Agency may need to convene a Small Business Advocacy Review Panel before taking any significant regulatory action. EPA will request nominations to serve as small entity representatives as part of a possible Small Business Advocacy Review Panel soon. If necessary, this process will inform the formal proposed rule.

EPA plans to issue a proposed rule for ethylene oxide commercial sterilizers in the coming months. The proposal will seek public comment, and EPA will hold a public hearing.