In spite of the opposition from truckers, California’s Air Resources Board voted unanimously Friday to adopt the nation’s toughest rules on heavy duty trucks - requiring retrofitting or replacement of older rigs, to crack down on diesel air pollution.
The federal government is forcing new diesel trucks to carry far cleaner engines by 2010. The new rules, which take effect in 2011, would cover any trucks that travel through California, no matter where they are registered. Owners would be required to retrofit about 230,000 heavy duty rigs with diesel exhaust traps and replace about 350,000 older, dirty engines over the next 15 years.
State officials say existing trucks must be phased out in order to meet federal mandates to clean California’s air - particularly in the heavily polluted South Coast Basin and San Joaquin Valley. The state has the dirtiest air in the nation, and diesel trucks are responsible for one-third of the smog.
Though the truckers said the new rules will force them out of business and they would be bankrupted in a sinking economy, the Board declared that the health benefits far outweigh the financial pain. 
According to representatives of the American Academy of Pediatrics, the American Lung Assn., the California Medical Assn., which endorsed the rules, diesel exhaust can cause lung and heart disease, cancer and premature deaths. Board economists said the measure will save Californians up to $68 billion in healthcare costs in 15 years.
Chairman Mary Nichols said: “This is an industry that has an enormous impact on people’s lives. This regulation will save more than 9,000 lives and reduce the toxic emissions that cause cancer and birth defects.”