Mack MP7 and MP8 engines have been certified to meet California's 2008 criteria to limit emissions of nitrogen oxides (NOx) while idling.

This means Mack customers with compliant engines will not have to shut down their engines after five minutes of idling as otherwise required by California regulations that took effect earlier this year.

The California Air Resources Board requires trucks to stop idling after no more than five minutes, under most circumstances. However, trucks with engines which emit 30 grams or less per hour of NOx are not required to shut down and can continue to idle. Several other states intend to pursue adoption of California's idle regulations in the near future.

Customers now have the option to specify "Idle Emission Certification - CARB 08" for Mack MP Series engines built after January 1, 2008. This feature means the truck's engine has been certified to meet the 30 gram/hour NOx limit. A CARB-required decal affixed to its hood identifies the truck as meeting the regulation. The new Mack MP10 engine will also be able to meet this standard when it goes into production later this year. Mack customers can order this feature from their dealers now.