Code Orange or Code Red days -- those times authorities tell us our air is unhealthful -- could jump dramatically this spring and summer.

That's because a tougher federal limit on ozone, the main pollutant in smog, is in effect.

The change means pollution levels that were just barely OK in the past will trigger high-ozone alerts now.

"The air is not getting dirtier," said Bill Hayden, a spokesman for the state Department of Environmental Quality. "We are simply looking even more closely for what pollution is out there."

Glen Besa, president of Virginia's Sierra Club chapter, said the increase in high-ozone days will reveal the true quality of the region's air.

"To the extent that we are having more Code Red or Code Orange days, that means we have been breathing unhealthy air all this time," Besa said.

The DEQ asks people to carpool, among other things, to hold down pollution levels on high-ozone days.

Code Orange means the air is moderately unhealthful -- mainly a problem for people with breathing troubles. Code Red days are more serious and can cause breathing problems even for healthy people.

For more than a decade, the nation's air was considered unhealthful when ozone hit 85 parts per billion or more, averaged over eight hours.

The Richmond region violated that limit seven times in 2007, nine in 2006 and six in 2005.

In March, the U.S. Environmental Protection Agency announced the new limit, 75 parts per billion. The DEQ estimates the Richmond area could violate that limit 25 times.

But Richmond's air actually is getting cleaner, Hayden said. For example, the region exceeded the old, less-stringent limit 25 times in 1999, 28 times in 1998, and 21 times in 1997.

The improvement largely is the result of programs that included a 2004 federal crackdown on power plants and factories in the eastern United States, Hayden said.

Dr. Kevin R. Cooper, a VCU Medical Center lung-disease expert, concurred that the region's air now is "pretty clean."

But ozone levels we get on hot, stagnant summer days can be high enough to cause breathing problems in healthy people working or exercising outdoors and to send asthmatics seeking the shelter of air-conditioned rooms, Cooper said.

Because of the tougher ozone limit, the region will have to do more to clean its air. Possible options include requiring sales of less-polluting paints, which could cost a few pennies more per gallon.

Measures already in place include the required sales of a cleaner-burning gasoline, which can cost up to 10 cents per gallon more than ordinary gas.

Ozone forms when the sun cooks pollutants from cars, smokestacks, lawn mowers and other sources. It typically is a warm-weather problem.

The air in Richmond and other parts of the state violated the new limit April 18. Since then, cool, wet weather has helped keep ozone levels down.

The Richmond area, as defined by the EPA, encompasses the cities of Richmond, Hopewell, Petersburg and Colonial Heights and the counties of Henrico, Hanover, Chesterfield, Charles City and Prince George.
Contact Rex Springston at (804) 649-6453 or rspringston@timesdispatch.com.