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Technology Transfer Network - OAR Policy and Guidance





  • On October 18, 2005, the Environmental Protection Agency (EPA) proposed no changes to the rule that limits emissions of toxic air pollutants from ethylene oxide sterilization facilities. This proposed rule is posted at: https://www3.epa.gov/ttn/oarpg/t3pfpr.html.
  • Commercial sterilization facilities use ethylene oxide to sterilize heat- and moisture-sensitive products and as a fumigant to control microorganisms or insects. There are approximately 100 of these facilities in the U.S. covered by this proposal.
  • EPA issued national rule to limit emissions of toxic air pollutants from these facilities in 1994. This rule is one of 96 rules called maximum achievable control technology (MACT) standards that require 174 industry sectors to eliminate 1.7 million tons of 188 toxic air pollutants. Congress listed these toxic air pollutants in the Clean Air Act (CAA).
  • EPA issued a final rule to limit air emissions of ethylene oxide from these facilities in 1994. The rule reduced emissions by approximately 1,000 tons per year or 90 percent.
  • The CAA now requires EPA to assess the risk remaining (residual risk) after the application of MACT. The 1994 national emission standards applied MACT to both large and small sources and general available control technology (GACT) applied to the vents at small sources.
  • Also, EPA must review and revise the air toxics standards as necessary by taking into account developments in practices, processes, and control technologies.
  • We are proposing no further action at this time to revise the national emission standards." The CAA requires EPA to regulate air toxics from large industrial facilities in two-phases.
    • Our initial risk assessment found that the chronic cancer, non cancer, and acute risks to humans, as well as ecological effects from these facilities are low enough that further controls are not warranted. In our analysis we used a health value for ethylene oxide developed by the State of California. EPA is currently developing a health value which, if completed in time for the court-ordered promulgation, will be incorporated into the analysis.
    • In our technology assessment we did not find any advancement in practices, processes, and control technology.
  • Today's proposal announces EPA's decision and requests public comments on the residual risk assessment and technology review for the national emission standards.
  • A 60-day comment period will begin at the date of publication of this proposal in the Federal Register.

  • The CAA requires EPA to regulate air toxics from large industrial facilities in two-phases.
  • The first phase is "technology-based," where EPA develops standards for controlling the emissions of air toxics from sources in an industry group (or "source category"). These MACT standards are based on emissions levels that are already being achieved by the better-controlled and lower-emitting sources in an industry. EPA finalized the Gas Distribution and Pipeline Breakout Station MACT standards in December 1994.
  • Within 8 years of setting the MACT standards, EPA is required to assess the remaining health risks from each source category to determine whether the MACT standards appropriately protect public health. In applying this "risk-based" approach - called residual risk - EPA must determine whether more health-protective standards are necessary.
  • To decide whether additional regulation under residual risk was necessary, EPA applied the two-step decision process described in the 1989 Benzene National Emissions Standards for Hazardous Air Pollutants. With this process EPA first determines if the risk to the individual most exposed is acceptable and then if the exposed population is protected with an ample margin of safety. This decision framework is further described in both the EPA's Residual Risk Report to Congress at https://www3.epa.gov/ttn/oarpg/t3/reports/risk_rep.pdf, and in the Air Toxics Risk Assessment Reference Library (https://www.epa.gov/ttn/fera/risk_atoxic.html).
  • Also, every 8 years after setting the MACT standards, the CAA requires that EPA review and revise them, if necessary, to account for improvements in air pollution controls and or prevention.
  • Interested parties can download the notice from EPA's web site on the Internet under recently signed rules at the following address:https://www3.epa.gov/ttn/oarpg/ramain.html.
  • Today's proposed amendments and other background information are also available either electronically in EDOCKET, EPA's electronic public docket and comment system, or in hardcopy at EPA's Air and Radiation Docket and Information Center, Environmental Protection Agency, Room B102, 1301 Constitution Avenue, NW, Washington, D.C. (Docket ID No. OAR-2004-0019). The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air and Radiation Docket and Information Center is (202) 566-1742.
  • HOW TO COMMENT: Comments will be accepted for 60 days beginning when this proposal is published in the Federal Register. All comments should be identified by Docket ID No. OAR-2004-0019 and submitted by one of the following methods:
    • Federal eRulemaking Portal ( http://www.regulations.gov );
    • EDOCKET ( https://www.epa.gov/edocket );
    • E-mail ( a-and-r-docket@epa.gov );
    • Facsimile ((202) 566-1741);
    • Mail (Air and Radiation Docket and Information Center, Environmental Protection Agency, Mailcode: 6102T, 1200 Pennsylvania Avenue, NW, Washington, DC 20460); or
    • Hand delivery (Air and Radiation Docket and Information Center, Environmental Protection Agency, Room B102, 1301 Constitution Avenue, NW, Washington, DC).
  • For additional information, visit the EPA's website at:, https://www.epa.gov/ttn/atw/eo/eopg.html or or contact David Markwordt of the EPA's Office of Air Quality Planning and Standards at (919) 541-0837 or by e-mail at markwordt.david@epa.gov.

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