EPA sets emissions test margins, adopts program changes

The Environmental Protection Agency has established final emissions measurement accuracy margins for in-use testing of heavy-duty diesel engines and adopted several changes to the in-use testing program, primarily in response to concerns from engine manufacturers.

In addition to the accuracy margins for in-use testing, the direct final rule makes several changes to the program in the early years of testing. EPA is eliminating the first year – 2006 – of the two-year pilot program for particulate matter (PM) emissions in response to engine manufacturers’ concerns over the availability of portable measurement systems (PEMS) for that pollutant.

Also, due to the delay in developing the final accuracy margin for PM under the aforementioned comprehensive research program, EPA is delaying the first year of the fully enforceable PM test program from the 2008 calendar year to the 2009 calendar year. Pilot program testing will continue during 2008.

Finally, EPA extended the normal period for reporting in-use test results during the initial years of the program and allowed certain short-term changes in how vehicles are recruited and tested.

EPA said its changes are intended primarily to adjust to delays in initiating the gaseous emissions and PM pilot programs, as well as manufacuturers’ concerns regarding the schedule for initial purchases of PM measurement systems and regarding potential difficulties in installing the necessary devices.

EPA executed the changes in a direct final rule published today in the March 13 Federal Register. Federal agencies publish direct final rules without prior public comment when they view the action as noncontroversial. To cover its bases, however, EPA separately published a notice of proposed rulemaking (NPRM) in the same issue of the Federal Register.

To view the direct final rule and NPRM, visit www.regulations.gov and search EPA-HQ-OAR-2004-0072.