Transportation
California toughens emission standards
California regulators voted Dec. 9 to end a voluntary program and instead force owners of nearly 60,000 heavy-duty trucks, school buses and diesel-powered motor homes to upgrade computer software to reduce engine emissions.
The California Air Resources Board regulation applies to vehicles built between 1993 and 1999. The board acted after a seven-month voluntary trial program was unsuccessful in upgrading enough trucks.
The mandatory reflash program will require the oldest trucks, 1