Cars With California Emissions Control Systems Not Needed in Pennsylvania

"Existing federal emission limits will eliminate almost all remaining automobile air pollution during the next two decades. Adopting California's requirements would cost Pennsylvanians a bundle, while conferring imperceptible environmental benefits."

"States have a choice when it comes to emission standards for new automobiles: federal or California. Under federal requirements, total air pollution from Pennsylvania's cars will decline about 80 percent over the next 20 years. With California standards, the decline would be 82 percent. The air will be clean either way."

"Here's the trick: To simplify the calculations, let's say Pennsylvania's automobiles currently put 100 tons of pollution into the air each day. Over the next 20 years, federal standards will get rid of 80 tons, or 80 percent, so that 20 tons per day remain. California’s standards would get rid of 82 tons, or 82 percent, leaving 18 tons remaining."

"Eighteen tons is 10 percent less than 20 tons. This is the source of The Patriot-News' claim of the benefits of California’s requirements. But the difference between 20 and 18 tons is only 2 percent of the current baseline of 100 tons, which is the appropriate baseline for measuring future improvements."

Thanks to C. P. Zilliacus