Skip to content U.S. Department of Transportation/Federal Highway AdministrationU.S. Department of Transportation/Federal Highway Administration
Office of Planning, Environment, & Realty (HEP)

Transportation Conformity Highlights

March 2006

EPA Releases Final Transportation Conformity PM Hot-Spot Rule. On March 10, 2006, the EPA released the final PM Hot-Spot Rule that includes the criteria for determining which transportation projects must undergo a local air quality analysis as part of conformity determinations in PM2.5 nonattainment areas. The final rule also streamlines existing hot-spot requirements in PM10 areas. The final rule requires that PM2.5 or PM10 hot-spot analyses be performed only for projects of air quality concern. Examples of such projects include intermodal freight or bus terminals, and major highway projects and congested intersections involving significant diesel traffic. No PM2.5 or PM10 hot-spot analyses will be required for projects that are not of air quality concern. To access the final rule see: The complete transportation conformity regulations that incorporate the March 10, 2006 final rule and all previous rulemakings is available for download at FHWA's website:

EPA Announces Final Air Quality Criteria for Ozone and Other Photochemical Oxidants. On February 28, 2006 EPA issued a Federal Register Notice on the availability of Air Quality Criteria for Ozone and Other Photochemical Oxidants. The final document is available on EPA's website at: The Criteria Document is a compilation and evaluation by U.S. EPA scientific staff and other expert authors of the latest scientific knowledge relevant to assessing the health and welfare effects of ozone. The document presents the latest available pertinent information on atmospheric science, air quality, exposure, health effects, and environmental effects of ozone and other related photochemical oxidants. This document leads to the next step which is that EPA's Office of Air Quality Planning and Standards (OAQPS) prepares a staff paper that bridges the gap between scientific assessments in the criteria document and judgments required of the EPA Administrator in evaluating whether to retain or revise the Ozone NAAQS. The final rule will be issued in the Federal Register. For further information about this process see:

HPMS study to look at changing business needs. In light of the recent authorization of SAFETEA-LU and the changing business needs of both our internal and external customers, the FHWA Office of Highway Policy Information is about to undertake a periodic reassessment of the Highway Performance Monitoring System. The HPMS' purpose has always been to provide data that reflects the extent, condition, performance, use, and operating characteristics of the Nation's highways. It is also the data used to calculate the vehicles miles of travel (VMT), a key data item when used in establishing regional transportation-related emissions for transportation conformity purposes.

To identify the changing needs for accurate, appropriate, and timely data related to meet HPMS' purpose, the FHWA is conducting a reassessment process to determine what improvements may be necessary to maintain and enhance this national highway database.

A series of regional outreach meetings will be held to seek input and generate discussion of what direction HPMS should take by the year 2010. Findings will be documented and recommendations will be formulated on behalf of these meetings and other public comment. These meetings are to be held in Washington, DC (April 10-11, 2006), Hartford, CT (April 26-27, 2006), Atlanta, GA (May 10-11, 2006), Portland, OR (May 24-25, 2006), and Lincoln, NE (May 31-June 1, 2006). The entire reassessment is expected to take 18 months. All interested, including State Highway Agencies, MPO's, regional councils, consultants, academia, and others that make use of highway data are encouraged to take part. For more information, please contact Ralph Volpe at 202-366-4048 or visit our website at

FHWA releases "An Introduction to Particulate Matter for Transportation Officials." FHWA's Office of Natural and Human Environment and the Resource Center have developed a brochure that discusses the basics of particulate matter and transportation conformity under the PM2.5 and PM10 national ambient air quality standards. It is intended as a resource for State and local transportation officials as well as other stakeholders. The brochure will be available shortly at:

FHWA Resource Center to Hold PM2.5 Hot-Spot Webcast. The FHWA Resource Center will be offering a webcast on PM2.5 Hot-Spot qualitative guidance soon. The workshop is specifically designed for project sponsors and FHWA Division staff that will need to know how to conduct PM2.5 qualitative hot-spot analysis. For more information and latest schedule see:

AMPO Air Quality Work Group to Meet in Oakland, CA. On April 3 and 4, the AMPO Air Quality Work Group will meet in Oakland, CA. The first day of the meeting, a tour has been arranged at a local diesel retrofit facility for interested Air Quality Work Group members and meeting participants. Contact Rich Denbow at or Sarah Siwek at for information.

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 can be found at:

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

FHWA Resource Center Air Quality Team Contacts:

Updated: 11/3/2014
HEP Home Planning Environment Real Estate
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000