2005 Not-to-Exceed (NTE) and Euro III European Stationary Cycle (ESC) Supplemental Test Procedures

This page last reviewed January 5, 2005

Heavy-duty diesel engines are used in vehicles with a gross vehicle weight rating of 14,001 pounds and greater. The primary pollutants of concern from diesel engines are oxides of nitrogen (NOx) and particulate matter. The high temperatures and excess air cause the nitrogen in the air to combine with available oxygen to form NOx.
The current certification requirements for new heavy-duty diesel engines produced for sale in California are based on compliance with emission standards under conditions specified by the Federal Test Procedure (FTP). In the 1990s, it was found that seven of the largest heavy-duty diesel engine manufacturers violated certification regulations by turning off, or defeating, emission control devices during in-use highway driving. Consequently, the Department of Justice, U.S. EPA and the Air Resources Board signed consent decrees with the seven engine manufacturers. The settling manufacturers are required, among other things, to produce heavy-duty diesel engines that meet a 2.5 g/bhp-hr FTP limit on non-methane hydrocarbons plus NOx emissions no later than October 1, 2002. The majority of these settling manufacturers, have also agreed to produce engines by October 1, 2002 that meet supplemental certification procedures including the NTE test and the ESC test. The consent decrees stipulate that these requirements must be met for a period of two years. Together with the FTP test, these supplemental test procedures will require control of emissions over the majority of real world conditions.
When the consent decree requirements expire in 2004, adopting the proposed test procedures will require settling manufacturers to continue producing clean engines during the 2005 and 2006 calendar year period, and require non-settling manufacturers to produce similarly clean engines beginning in 2005.


Formal Regulatory Documents Click here to view the formal regulatory documents. These documents include, butare not limited to, the staff report, hearing notice and 15-day notice(s).
December 7, 2000 Public Hearing Presentation from the December 7, 2000 Public Hearing (PDF - 988K)

For more information, you can contact Stephan Lemieux via email or at (626) 450-6162.
On-Road Heavy-Duty Vehicles