The EPA issued tighter smog standards yesterday, limiting ground-level ozone to 70 parts per billion from 75 ppb.

The agency says the updated National Ambient Air Quality Standards will reduce the public’s exposure to ozone pollution and says the public health benefits of the updated standards, estimated at $2.9 to $5.9 billion annually in 2025, outweigh the estimated annual costs of $1.4 billion.

While the new smog standards aren’t as stringent as they could have been — the EPA originally proposed strengthening the air quality standards to within a range of 65 ppb to 70 ppb while taking comment on a level as low as 60 ppb — the National Association of Manufacturers immediately issued a statement calling the rule “overly burdensome, costly and misguided.

“After an unprecedented level of outreach by manufacturers and other stakeholders, the worst-case scenario was avoided,” said NAM president and CEO Jay Timmons. “But make no mistake: the new ozone standard will inflict pain on companies that build things in America—and destroy job opportunities for American workers.”

Nationally, from 1980 to 2014, average ozone levels have fallen 33 percent, according to EPA estimates.

The agency also strengthened the “secondary ozone standard” to 70 ppb, which it says will improve protection for trees, plants and ecosystems.

The Clean Air Act provides states with time to meet the standards. Depending on the severity of their ozone problem, areas would have until between 2020 and 2037 to meet the standards.