WASHINGTON (AP) — The Environmental Protection Agency is proposing a federal plan that would restrict smokestack emissions from power plants and other industrial sources that burden downwind areas with smog-causing pollution they can't control.

The plan announced Friday is intended to help more than two dozen states meet "good neighbor" obligations under the federal Clean Air Act.

States that contribute to ground-level ozone, or smog, are required to submit plans ensuring that coal-fired power plants and other industrial sites don't contribute significantly to air pollution in other states. In cases where a state has not submitted a "good neighbor" plan — or where EPA disapproves a state plan — the federal plan would take effect to ensure downwind states are protected, the EPA is now proposing.

"Air pollution doesn't stop at the state line," EPA Administrator Michael Regan said in a statement. The new federal plan "will help our state partners meet air quality health standards, saving lives and improving public health in smog-affected communities across the United States," he said.

A 2015 rule set by EPA blocks states from adding to ozone pollution in other localities. The rule applies mostly to states in the South and Midwest that contribute to air pollution along the East Coast. Some states, such as Texas, California, Pennsylvania, Illinois and Wisconsin, both contribute to downwind pollution and receive it from other states.

Ground-level ozone, which forms when industrial pollutants chemically react in the presence of sunlight, can cause respiratory problems, including asthma and chronic bronchitis. People with compromised immune systems, the elderly and children playing outdoors are particularly vulnerable.

A report last year by the American Lung Association found that more than 123 million Americans lived in counties that experienced repeated instances of unhealthy ozone levels. Climate change is likely to exacerbate the problem by causing more hot sunny days conducive to high ozone levels.

The EPA rule set a standard of 70 parts per billion, a level that some environmental and health groups argued falls short. Business leaders and Republicans said the Obama-era rule could harm the economy and cost jobs.

The Trump administration moved to weaken the rule, but the EPA under President Joe Biden said it was restoring pollution controls on power plants and industrial sites.

The cross-state pollution rule "protects millions of Americans across the Eastern U.S. from smog that blows across state lines and then permeates their communities,'' said Graham McCahan, a senior attorney for the Environmental Defense Fund.

The proposed update "will encourage more power plants to invest in clean, affordable zero-emitting power, which will help more upwind states be 'good neighbors' as the Clean Air Act requires,'' McCahan said.

"While the intent of this proposal is right and one that we share, it could have significant effects on American families if not thoughtfully implemented,'' said Aric Newhouse, vice president of the National Association of Manufacturers.

"At a time when our supply chains are snarled, inflation is skyrocketing and Russia's war on Ukraine continues, we must be careful with regulations that could further raise prices on all Americans, slow economic growth and threaten jobs,'' he said.

Manufacturers will work with EPA to ensure the rules can "achieve shared goals in a constructive way," Newhouse said.

The EPA proposal would affect power plants starting next year and industrial sources in 2026. The plan would cover engines used in natural gas pipeline; cement kilns; boilers and furnaces in iron and steel mills; glass manufacturers; and boilers used in chemical, petroleum, coal and paper plants.

The proposed rule includes a 60-day public comment period. EPA expect to issue a final rule by the end of the year.