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FACT SHEET: Amendments to Final Standards

Reciprocating Internal Combustion Engines


  • On March 2, 2011, the Environmental Protection Agency (EPA) issued a direct final rule and parallel proposal to amend the rule limiting toxic air pollution from stationary reciprocating internal combustion engines (RICE).
  • This direct final action and parallel proposal clarifies compliance requirements related to continuous parameter monitoring systems (CPMS). Specific changes EPA is making include the following:
    • Providing an additional 180 days for sources to comply with the CPMS operation and maintenance requirements;
    • Revising the frequency of the temperature measurement device performance check from quarterly to annually; and
    • Correcting an inadvertent error in the averaging time for the continuous parameter data.
  • This action also corrects minor typographical errors in the regulatory text to the August 2010 rule.
  •  EPA is publishing these changes as a direct final rule because the changes are noncontroversial and no adverse comments are anticipated. If adverse comments are received, EPA will address the comments in a subsequent final rule based on the parallel proposal that is being issued in conjunction with the direct final rule amendments.
  • These direct final rule technical amendments will be effective 60 days after publication of the direct final rule in the Federal Register.


  • In August 2010, EPA issued a final rule to limit emissions of air toxics from existing stationary engines located at major and area sources. The final rule included operation and maintenance requirements for CPMS.
  • EPA received a request for an administrative stay of two provisions of the August 2010 final rule relating to the operation and maintenance requirements for CPMS. On January 19, 2011, EPA granted a 90-day stay of two paragraphs in the regulatory text of the final rule.


  •  EPA will accept public comments for 30 days after the direct final action and parallel proposal are published in the Federal Register.
  •  Comments should be identified by Docket ID No. EPA-HQ-OAR-2008 -0708 and submitted by one of the following methods:
    •  Federal eRulemaking Portal (
    • e-mail (
    • Mail (EPA Docket Center, Environmental Protection Agency, Mail code 6102T, 1200 Pennsylvania Avenue, NW, Washington, DC 20460), or
    • Hand delivery (EPA Docket Center, Environmental Protection Agency, Room 3334, 1301 Constitution Avenue, NW, Washington, DC).


  • The direct final rule and parallel proposal is posted at:
  • Today’s action and other background information are also available either electronically at, EPA’s electronic public docket and comment system, or in hardcopy at the EPA Docket Center’s Public Reading Room.
  •  The Public Reading Room is located in the EPA Headquarters Library, Room Number 3334 in the EPA West Building, located at 1301 Constitution Ave., NW, Washington, DC. Hours of operation are 8:30 a.m. to 4:30 p.m. eastern standard time, Monday through Friday, excluding Federal holidays.
    •  Visitors are required to show photographic identification, pass through a metal detector, and sign the EPA visitor log. All visitor materials will be processed through an X-ray machine as well. Visitors will be provided a badge that must be visible at all times.
    •  Materials for this action can be accessed using Docket ID No. EPA-HQ-OAR-2008-0708.
  • For further information about the action, contact Ms. Melanie King of EPA’s Office of Air Quality Planning and Standards, Sector Policies and Programs Division, Energy Strategies Group at (919) 541-2469 or by e-mail at

Printable version of the fact sheet

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