Panel Grapples With Limits of EPA Particulate Matter Rule Review

A trio of judges at the US Court of Appeals for the District of Columbia Circuit heard arguments on Monday over whether recent changes to particulate matter air regulations flew against Clean Air Act procedure.

Republican-led states and industry challengers sued the agency in March, arguing that the more stringent ambient air limits, upped from 12 to 9 micrograms per cubic meter daily, are set beyond what is required to protect public health.

The Environmental Protection Agency is tasked under the Clean Air Act to set limits on pollutants in the ambient air that pose a national threat to public ...