Smog Check, a critical program for cutting tailpipe exhaust coast to coast, needs an overhaul because it fails to cut emissions sufficiently and doesn't concentrate on the dirtiest cars, according to a new study released Wednesday by the National Research Council.
The program, mandatory in many states, requires motorists to have their cars tested for excessive emissions and make necessary repairs. Smog Check is one of the few anti-smog measures that affect almost every driver and put the onus on them to pay for pollution cleanup.
The study found that most states are only achieving half or less of the anticipated emission reductions from cars and trucks. The findings call into question the effectiveness of local and state clean-air plans, the study says.
The findings by a panel of experts assembled by the National Research Council, an arm of the National Academy of Sciences, provide a comprehensive overview of how states administer the program, which is required in smoggy regions. Congress sought the review based on similar conclusions in other surveys, including one last year by the California Air Resources Board.
Despite the shortcomings in Smog Check, however, the panel says the program should be improved and not scrapped. Vehicles produce more than 70% of the smog-forming emissions in the Los Angeles region and about 50% nationwide. Smog Check is the only pollution control program that targets cars after they have left the assembly line.
"Inspection and maintenance programs should focus on repairing the worst polluting vehicles and verifying repairs, but in ways that are both cost-effective for states and not overly burdensome for owners," said UC Irvine Chancellor Ralph J. Cicerone, who chaired the committee that wrote the report. "We also need better methods of evaluating the impact of these programs, but having said that, it's important to emphasize that these programs are absolutely necessary to reduce harmful auto emissions and achieve better air quality."
In the report, investigators found too much attention focused on new cars, which typically run very clean, and not enough attention on the dirtiest cars. Old models account for only 10% of all cars, but they produce about half the emissions. As many as 1 in 4 dirty cars never pass the test, but many of them remain on the road, the study shows.
But concentrating on the dirtiest cars would be a burden for low-income motorists driving older cars, who would be required to bear a greater share of cleanup costs.
In California, state officials exempt 1998 to 2001 model cars from smog checks while providing subsidies of up to $1,000 to destroy high-emission older cars, said Glenn Mason, spokesman for the Department of Consumer Affairs, which oversees the state's Smog Check program.
"California's Smog Check program is leading the way. It's in the vanguard," Mason said. "We target gross polluting vehicles and provide consumers assistance."
However, a study by the state Air Resources Board last year found that the state's Smog Check program achieved only 40% of the cut in emissions it is supposed to reach. The program is required to reduce emissions by 112 tons daily but accomplishes a reduction of only 45 tons, the state's report shows.