The FirstEnergy Corp. W.H. Sammis coal-fired power plant on the Ohio River in Stratton, Ohio, in 2017.
CNN  — 

A group of Republican-led states, fossil fuel industry groups and utilities filed an emergency request with the Supreme Court Wednesday, asking it to block the implementation of the Biden administration’s “good neighbor” rule – a regulation to cut down on harmful smog and air pollution that wafts downwind and across state lines.

The Clean Air Act requires the Environmental Protection Agency to occasionally review and revise the interstate pollution rule to make sure it aligns with the latest health guidelines and science. The EPA strengthened the rule in March under a court-ordered deadline, after it languished without update during the Trump administration.

The revision required 23 states that weren’t meeting the requirements to adhere to the rule, which prevents smog and air pollution from power plants and heavy industry from floating into other states and worsening air quality. For instance, if one state generating ozone and smog through its coal-fired power plants sends these pollutants into another neighboring state, it could be in violation of the rule.

The rule is being challenged in multiple courts, but so far none of those cases have successfully blocked it. In their application to the Supreme Court, the Republican states and industry groups say the Biden EPA plan threatens the reliability of the nation’s electric grid. The court will likely ask for a response from the EPA before taking action on the request.

“The plan inflicts irreparable, economic injuries on the States and others every day it remains in effect,” petitioners wrote on Wednesday. “Worse still, the plan is likely to cause electric-grid emergencies, as power suppliers strain to adjust to the federal plan’s terms. To prevent these harms, the Court should step in now.”

CNN has reached out to the EPA for comment.

To adhere to the updated rule, heavy industry and power plants will need to be outfitted with specialized pollution control equipment and run it throughout peak ozone season, which varies state to state. The rule is part of a suite of EPA rules that both cut down on pollution that can be harmful to human health, but also have the effect of cutting down on planet-warming pollution from coal-fired power plants.

“If it’s allowed to be fully implemented, this clean air rule will reduce asthma symptoms for millions of Americans, keep thousands of people out of the hospital, and save over a thousand lives each year,” Kathleen Riley, an attorney for the nonprofit environmental litigation group Earthjustice, said in a statement. “None of the rule’s protections should be put on hold.”