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Nonroad Engines, Equipment, and Vehicles



Contrails are line-shaped clouds or “Condensation trails” composed of ice particles that are visible behind jet aircraft engines under certain atmospheric conditions and at times can persist. EPA is not aware of any deliberate actions to release chemical or biological agents into the atmosphere. If you have a question, please email us at otaq@epa.gov (or call the contrail information line at 734-214-4432 to hear this message).

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This page provides information about air pollutant emissions from aviation. It includes regulations, guidance, and other information related to aircraft.

Notice of Updates regarding the Public Hearing on the Proposed GHG Endangerment and Contributions Findings for Aircraft under Section 231 of the Clean Air Act

The EPA has issued a Supplemental Notice in the Federal Register which provides three updates regarding the public hearing which is scheduled for August 11, 2015 in Washington DC. First, it corrects a typographical error in the street address for the public hearing and provides notice of availability of a conference call-in number for the public to listen to the hearing. Additionally, this action provides notice that video recording will be allowed in the hearing room provided that it does not interfere with or interrupt the public hearing.

Notice of Updates to Public Hearing (PDF) (2 pp, 200K, published July 29, 2015)

Notice of Public Hearing on the Proposed GHG Endangerment and Contribution Findings for Aircraft under Section 231 of the Clean Air Act

EPA will hold a public hearing on this Proposal on Tuesday, August 11, 2015 in Washington, D.C. The hearing will be held at the U.S. EPA Offices, the William Jefferson Clinton East Building, Room 1153, 1201 Constitution Avenue, NW and will start at 10 am local time.

Speakers should contact Ms. JoNell Iffland to request to speak at the hearing. Speakers are encouraged to pre-register. The last day to preregister in advance to speak at the hearing will be August 6, 2015.

    Ms. JoNell Iffland
    Office of Transportation and Air Quality
    Assessment and Standards Division (ASD)
    Environmental Protection Agency
    2000 Traverwood Drive
    Ann Arbor, Michigan 48105
    Telephone number: (734) 214-4454
    Fax number: (734) 214-4816
    Email address: Iffland.jonell@epa.gov.

Requests to speak will be taken on the day of the hearing at the hearing registration desk, and accommodated as time permits, although preferences on speaking times may not be able to be fulfilled. Oral testimony will be limited to no more than 10 minutes for each commenter, although we may need to adjust the time for each speaker if there is a large turnout. The EPA requests that commenters provide the EPA with 3 copies of their oral testimony in hard copy form the day of the hearing or an electronic copy in advance of the hearing date. Speakers are encouraged to pre-register.

For further information on the public hearing, including identification requirements for a Federal Building, please see section I.B of the Federal Register notice, 80 FR 37758 (July 1, 2015).

EPA Takes First Steps to Address Greenhouse Gas Emissions from Aircraft

The EPA proposed to find that greenhouse gas (GHG) emissions from certain classes of engines used in aircraft contribute to the air pollution that causes climate change endangering public health and welfare under section 231(a) of the Clean Air Act. At the same time, EPA issued an Advance Notice of Proposed Rulemaking that provides information on the process for setting international CO2 emissions standards for aircraft at the International Civil Aviation Organization, and describes and seeks input on issues related to setting an international CO2 standard for aircraft, and the potential use of section 231 of the Clean Air Act to adopt a corresponding aircraft engine standard domestically.

Fact Sheet: EPA Takes First Steps to Address Greenhouse Gases from Aircraft Engines (PDF) (4 pp, 167K, EPA- 420-F-15-023, June 2015)

Proposed Rule and Advanced Notice of Proposed Rulemaking (PDF) (50 pp, 884K, published July 1, 2015)

EPA Notifies ICAO of Timeframe for Initiating U.S. Domestic Process to Address Aircraft GHGs

The United States recently submitted an information paper to the United Nation’s International Civil Aviation Organization (ICAO) that sets out a timeframe for initiating the U.S. domestic regulatory process for addressing greenhouse gas emissions from aircraft under the Clean Air Act.

NOx Emissions from Commercial Aircraft Engines

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Lead Emissions from Piston-Engine Aircraft Using Leaded Aviation Gasoline

The EPA is evaluating the impact of lead emissions from aircraft using leaded aviation gasoline in order to make a determination regarding whether aircraft lead emissions cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare. These actions are in response to petitioners’ requests, which are provided below along with the EPA responses to date. The EPA currently intends to issue a proposed finding on the question of endangerment in 2017. This proposed finding will then undergo public notice and comment. After evaluating comments on the proposal, we plan to issue a final endangerment finding in 2018. Documents and information relevant to the EPA’s ongoing evaluation and other EPA activities regarding lead in air are provided below.

In separate activities related to the National Ambient Air Quality Standards for lead, EPA finalized revisions to the ambient monitoring requirements for measuring lead in the air on December 14, 2010. These amendments expanded the nation's lead monitoring network to better assess compliance with the 2008 National Ambient Air Quality Standards for lead. EPA required the continuation of monitoring at airports emitting at least one ton of lead per year. EPA also required the states to conduct a year-long monitoring study at 15 airports that emit less than one ton per year to determine how these sources impact air quality.

The following documents provide information on inventory documentation and additional data:

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