Tougher U.S. air-pollution rules, scheduled to take effect this summer, could put hundreds of millions of tax dollars at risk while ushering in lower speed limits, carpool lanes and tailpipe tests in areas with even marginally dirty air -- such as Central Florida.

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The U.S. Environmental Protection Agency is pushing to adopt more-stringent standards for ozone, a major component of smog and a health hazard, especially for children, the elderly and people with breathing ailments. Primary generators of the pollutant in Florida are cars, trucks and electric-power plants. The Bush administration refused two years ago to adopt ozone standards recommended by an EPA panel of experts known as the Clean Air Scientific Advisory Committee. But now, under President Barack Obama, the agency intends to set an ozone limit in the air we breathe of 60 parts per billion to 70 parts per billion. The current limit is 75 parts per billion, and records indicate that Central Florida typically checks in at 66 to 71 parts per billion.

Source: Will Florida get tailpipe tests, 55 mph speed limit to cut air pollution?