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Transportation Conformity Highlights

September 2006

Prepared by the Office of Natural and Human Environment Federal Highway Administration


EPA announced revised National Ambient Air Quality Standards for PM: On September 21, 2006, the U.S. Environmental Protection Agency announced the new National Ambient Air Quality Standards (NAAQS) for particulate matter (PM).

The final action calls for the strengthening of EPA's previous daily fine particle standard (PM2.5) from 65 micrograms of particles per cubic meter to 35 micrograms of particles per cubic meter of air. EPA is also retaining the current annual PM2.5 standard for long-term exposure to fine particles at 15 micrograms per cubic meter.

For the PM10 standard, EPA is retaining the existing daily PM10 standard of 150 micrograms per cubic meter. EPA is revoking the annual coarse particle standard because the available evidence does not suggest an association between long-term exposure to coarse particles at current ambient levels and health effects.

States must meet the revised standards by 2015, with a possible extension to 2020, depending on local conditions and the availability of controls. Later this month, EPA will issue guidance on monitoring fine and coarse particle pollution.

For more information about the final standards see:

Call for Papers - Transportation, Land-Use Planning, and Air Quality Conference 2007: The next in a series of Transportation Land-Use, Planning, and Air Quality Conferences will be held on July 9,10,11, 2007 in Orlando, Florida. The focus of the conference, which is jointly sponsored by several organizations, is the latest developments in transportation planning and land use modeling and new developments and strategies in air quality including transportation planning and land use planning processes that result in air quality benefits. The conference will focus on the technical and data implications of transportation land-use planning. Abstracts of 250 words or less should be submitted by November 20, 2006. For additional information see:

Training Opportunities

National Transit Institute Course: Introduction to Transportation Conformity. The NTI course, Introduction to Transportation Conformity has been updated to reflect SAFETEA-LU changes and new information about PM2.5 requirements. The course will be offered November 28-30, 2006 in Chicago, IL and in New York City on December 12-14, 2006. There will be two more course offerings between January and June 2007. For information see:

FHWA Resource Center Training Activities. FHWA's Resource Center Air Quality Technical Services Team is available to offer air quality-related training opportunities and information is available at:

If you have any suggestions for future monthly conformity highlights, please email:

FHWA Resource Center Air Quality Team Contacts:

Updated: 10/20/2015
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