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Edwards Lifesciences Añasco - Agency Response

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Why EPA is Reviewing Rules

As the U.S. Environmental Protection Agency (EPA) pursues its mission of protecting human health and the environment, addressing ethylene oxide emissions is a priority for the Agency. One of the ways EPA is doing that is by reviewing regulations for facilities that emit the chemical ethylene oxide. There are two regulations currently under review. These regulations are referred to as National Emissions Standards for Hazardous Air Pollutants (NESHAP). The Clean Air Act requires EPA to periodically review each NESHAP.

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Rules Currently Under Review

The NESHAP for Commercial Sterilizers was last reviewed in 2006. Commercial sterilizers use ethylene oxide to sterilize devices that cannot be sterilized using other methods, such as steam. Many medical devices are sterilized with ethylene oxide.

  • EPA has been gathering the data it needs to develop a proposed regulation, which the Agency expects to issue in mid-2020. Members of the public will have the opportunity to provide comments on the proposal.
    • In December, EPA  issued an Advance Notice of Proposed Rulemaking. That notice asked for information on strategies to reduce ethylene oxide emissions. The Agency also sent a Clean Air Act request for Information to several commercial sterilization companies that required them to provide information about their facilities, equipment used to reduce air pollution, and the cost of emission reductions. EPA will use the data it received from these requests to help develop the proposed rule.
    • Nearly one-third of the commercial sterilizers affected the rule are small businesses. Because of this, EPA is working with the Small Business Administration to convene a Small Business Advocacy Review Panel. The purpose of the panel is to gather advice and recommendations from small businesses likely to be regulated by an EPA rule.
  • After EPA issues a proposed rule, the proposal will be published in the Federal Register. People may read the proposed rule and submit comments on it.
  • EPA will review the comments and consider them as the Agency develops a final rule.

The NESHAP for Miscellaneous Organic Chemical Manufacturing also was last reviewed in 2006. This rule is often referred to as “the MON.” The rule applies to certain equipment and processes at of chemical plants. Some of the equipment and processes emit ethylene oxide, among other chemicals.

  • EPA is under a court order to review the MON. The Agency must issue a final rule by May 29, 2020.
    • In December, 22019, the Agency issued proposed amendments to the rule. The Agency held two public hearings in January 2020.
    • On February 19, 2020, the U.S. District Court for the District of Columbia gave EPA additional time to complete the rulemaking.
    • The public has until March 19, 2020 to submit comments on the proposal.

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For more information

EPA posts the latest information about the two rules to these two web pages:

Documents related to the review of the sterilizers rule are available at:

Documents related to the review of the MON are available at:

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