The new regulation applies to current and future trucks, and will go into effect in 2008.

According to ARB estimates, some 180,000 big-rig trucks operate on California roads each day emitting about 53 tons per day (tpd) of smog-forming oxides of nitrogen (NOx) and 0.73 tpd of particulate matter (PM).

About one quarter of those trucks are registered outside of California with 90% of those vehicles equipped with sleeper cabs. In addition to benefiting air quality, the new rule is expected to help reduce fuel consumption and engine maintenance costs for trucks that are in compliance.

Idling emissions can be especially heavy at truck stops and also at warehouses, distribution centers and port terminals where loading and unloading of freight often requires drivers to wait, sometimes for hours. Fortunately several new technologies have been developed that provide for truck cabin cooling and heating when the truck’s main engine shut off. These technologies reduce harmful emissions, and reduce fuel use as well.

—Barbara Riordan, Acting ARB Chair

The rule is a follow-up to earlier regulations that limit idling but excluded diesel trucks with “sleeper berths” which frequently depend on idling for cabin climate control and to run appliances.

There are two parts to the new rule. The first component regulates new 2008 and subsequent model year heavy-duty diesel engines, requiring them to be equipped with a non-programmable engine shutdown system that automatically shuts down the engine after five minutes of continuous idling.

To avoid incorporating a new engine shutdown system, an engine manufacturer may alternately certify an engine to a NO_x idling emission standard of 30 grams per hour. ARB makes this option available because “it may be possible to control NOx emissions during idling.” The agency believes, however, that this option isn’t likely to become available prior to 2010 because that is when more advanced NO_x controls are expected to be used for all heavy-duty engines.

The second component regulates in-use sleeper cab-equipped trucks, including those registered out-of-state, requiring operators to shut off their engines before the five minute idling time is reached. The rule provides for the use of alternative technologies (such as auxiliary power unit (APU), fuel-fired heater, thermal energy storage system, and/or a power inverter/charger with an electrically driven heating and air conditioning system) to provide power for cab comfort (e.g., heating, cooling, etc.) and on-board accessories that would otherwise have required continuous idling of the vehicle’s main engine. These technologies have zero or very low pollution emissions.

Resources:

• Reducing Idling Emissions from New and In-Use Heavy-duty Trucks

• CARB staff Initial Statement of Reasons