EPA proposes stronger smog standards

The Environmental Protection Agency proposed to limit ground-level ozone -- also known as smog -- at a level between 60 and 70 parts of ozone per billion measured over eight hours, which would reverse a 2008 Bush administration decision that set standards at 75 ppb.

Tougher standards could hit factories and oil, gas and power companies, which would be required to reduce emissions of nitrogen oxides and other smog precursors. Smog forms when those emissions react with sunlight.

The EPA said the standard would cut healthcare and lost work costs by between $14 billion and $100 billion. It said the proposal would cost between $19 billion and $90 billion to implement.

Environmentalists said Thursday's move follows the recommendations of the EPA's own science advisors.

Frank O'Donnell, president of the nonprofit Clean Air Watch, said the proposal was a "breath of fresh air."

"If the EPA follows through, it will mean significantly cleaner air and better health protection," he added.

At least one industry group opposed the move. The American Petroleum Institute said the proposal "lacks scientific justification," adding that the oil and natural gas industry has invested more than $175 billion toward improving the environmental performance of its products and facilities.

The proposal must undergo 60 days of public comment before becoming final.

(Reporting by Timothy Gardner; Editing by Christian Wiessner)