RALEIGH — State air quality officials issued a code Orange warning for ground -level ozone Tuesday, which meant people sensitive to air pollution should limit outside activity. It also means the state has to make every effort to reduce ozone to avoid exceeding federal standards.

What the warning states is that this area is exceeding the EPA's federal air quality standards.

Throughout the Triangle the roadways are jammed with automobiles, a sign of the area's rapid expansion, but the Triangle's rapid growth is creating another growing pain -- higher ozone levels.

Tom Mather of the state's division of air quality is concerned about that. He's asking people to conserve energy on days when the ozone level is higher than normal.

"That could be driving less, combining trips, carpooling or turning up your thermostat slightly on hot days." said Mather.

Mather says the EPA has issued tighter federal standards for ozone levels. If states exceed the new levels, the EPA will impose tougher measures such as higher gas prices for cleaner fuel and tighter vehicle inspections for emissions.

"Right now, I think the estimate is that cleaner fuel could cost 8 - 10 cents a gallon more than the gas we've got right now," said Mather.

Mather says there are many ways to both avoid ozone and to prevent adding to them.