"Draft Letter From EPA Advisors Urges Tougher Ozone Standard"
"A draft letter from a U.S. EPA science advisory committee recommends a tight standard for how much ozone pollution can be in the air, recommending that the lower bound of the standard should be 60 parts per billion, much lower than the current standard. But the letter notes that committee members haven't made a decision on the upper bound of the ozone standard."