SAN FRANCISCO – The California Air Resources Board (CARB) on Oct. 20 will decide on new rules to prohibit big-rig trucks with sleeping berths from idling their diesel engines while parked, reported Reuters. The measure is drawing fire from industry groups and big carriers. If adopted, California would be the first state to require sleeper trucks to shut off their engines during layovers, trucking industry officials said. Operators idle their engines overnight at truck stops and rest areas to heat or cool the sleeping area and operate electrical appliances and charge batteries. In 2004 California ordered operators of commercial trucks and buses to shut off their engines after an idle time limit of five minutes, but the rule did not cover trucks with sleeper berths unless they were within 100 feet of a home or school. The new rule would go into effect for engines on 2008-model year trucks weighing more than 14,000 lbs. Trucks would have to be equipped with a system to automatically shut off the engine after five minutes. Owners of pre-2008 sleeper trucks may have to install an auxiliary power supply or some other equipment to provide heat or air conditioning for the cab. Some of those devices produce their own emissions and California performance standards also are proposed for this gear, CARB board said. Federal regulations require a driver must be off duty for 10 hours after working a 14-hour shift. Critics of the new rules say there are no efficient auxiliary power supplies currently available for sleeper trucks and a no-idling rule could threaten the safety of drivers who need to rest. Thomas Vandenberg, general counsel for Wisconsin-based Schneider National, said he was not aware of a current technology that could meet a proposed CARB rule to control nitrogen oxide emissions from cab devices during idling. The California Trucking Association supports some idling curbs but not for sleeper trucks, said Stephanie Williams, senior vice president of the CTA. “We have to be careful about looking at air pollution versus the safety of drivers. We support technologies that can provide auxiliary power, but we must balance health and safety,” she said in the Reuters report. An estimated 1 million to 1.5 million big-rig trucks travel on California highways, each emitting more than 5 lbs. a day of nitrogen oxide, the principal ingredient of smog and soot, according to CARB.