The EPA on Thursday lowered the national limit for ground-level ozone from 75 parts per billion (ppb) to 70 ppb. The agency last year released a draft rule that specified a range of 65-70 ppb, though it was said to be considering a limit of 60 ppb. A study by NERA Economic Consulting showed the 60 ppb limit would have cost the U.S. economy $270 billion and 2.9 million jobs per year between 2017 and 2040.
While the agency did not tighten the ozone limit as much as industry groups feared, many believe the economic impact will be dramatic nevertheless. The American Petroleum Institute called on Congress to block the new rules, noting that the 70 ppb standard would affect job growth in nearly one third of all counties in the U.S.
