Medical instruments laid out on a light blue surface

Ethylene Oxide Standards

Ethylene oxide (EtO) is a flammable and highly reactive gas that is used in more than 100 facilities nationwide to sterilize medical instruments and other products. Chronic contact with EtO is associated with cancer, reproductive effects and neurotoxicity. Emissions from facilities that use EtO are subject to national emission standards for hazardous air pollutants (HAP) under the Clean Air Act, which the Environmental Protection Agency (EPA) is required to review every eight years.

2017-2021

The EPA last conducted a review of HAPs for commercial sterilizers in 2006 and is now more than five years late in conducting the next required review.

  • December 2019

    In December 2019, the EPA published an advanced notice of proposed rulemaking requesting input as it considers proposing a future rulemaking addressing EtO emissions from commercial sterilization facilities. The proposal seeks information on available control technologies for reducing EtO emissions and on developments in practices, measurement, monitoring, and technologies for the control of EtO from commercial sterilization facilities.

  • February 2020

    In February 2020, a coalition of eleven attorneys general led by Illinois Attorney General Kwame Raoul submitted comments urging the EPA to adopt stricter standards for EtO emissions. In their letter, the attorneys general recommended the EPA reduce EtO air emissions by at least 99.9 percent, capture 100 percent of all generated EtO emissions, conduct all required emissions testing under actual operating conditions, monitor emissions continuously, and require each facility demonstrate that its emission reduction measures reduce the public health threat to workers and local communities.