A federal appeals court has ordered the Environmental Protection Agency (EPA) to revise its lead-paint standards within 90 days and write new rules within a year.

The 2-1 decision last week by the San Francisco-based Court of Appeals for the 9th Circuit came in response to environmental groups demanding that the EPA act upon a rulemaking petition it granted several years ago. The environmental groups involved in the legal action argued that the most up-to-date scientific research shows today’s standards for mitigating lead-based paint don’t go far enough to protect children. The court accepted that argument.

“The new information is clear in this record: the current standards for dust-lead hazard and lead-based paint hazard are insufficient to accomplish Congress’s goal” of reducing childhood exposure to lead, the court wrote in its opinion.

In their 2009 petition to the EPA, the environmental groups sought to reduce EPA’s lead-in-dust standard from 250 micograms per square foot to 100 micograms per square foot on interior window sills.

During oral arguments in June 2017, the EPA said it would take six years to develop new  lead paint rules. The court rejected that claim and ordered the agency to take immediate action.

“The panel held that the EPA was under a duty stemming from the Toxic Substances Control Act and the Residential Lead-Based Pain Hazard Reduction Act of 1992 to update lead-based paint and dust-lead hazard standards in light of the obvious need, and a duty under the Administrative Procedure Act to fully respond to petitioners’ rulemaking petition,” the court wrote in its opinion.

An EPA spokesperson told The Hill newspaper last week that the agency would review the ruling, adding that officials would “continue to work diligently on a number of fronts to address issues surrounding childhood lead exposure from multiple sources.”

It’s unclear how the court’s ruling could affect the controversial Lead: Renovation, Repair and Painting Rule (RRP), which the Window and Door Manufacturers Association (WDMA) and other industry groups have been working to overhaul for several years.

“We have read the ruling and at this time, WDMA’s focus continues to be on resolving the ongoing issues with the RRP rule’s implementation, including the lack of a commercially available test kit and reinstating the opt-out provision,” said Kevin McKenney, director of government affairs  with the WDMA. “We understand EPA has been instructed by the court to issue a proposed rule within 90 days, and we will be closely evaluating it when it is published.”

The EPA’s RRP rule requires any renovation work — including door and window replacements — that disturbs more than six square feet of a pre-1978 home’s interior to follow expensive work practices to protect residents from exposure to lead, which can be especially hazardous for little children. The work must be supervised by an EPA-certified renovator and completed by an EPA-certified renovation firm.

WDMA and other industry groups argue that the extra cost associated with lead-safety procedures prevents many homeowners  in older buildings from replacing their windows, which often aren’t energy-efficient. At its 2017 legislative conference in Washington, D.C., WDMA urged members of Congress to sign a letter to the EPA asking the agency to consider changes to the rule, such as restoring the opt-out provision for homes without a child under the age of six or a pregnant woman. The lack of an accurate test kit for lead paint is also an issue that WDMA wants the EPA to address.

According to the EPA, approved test kits for the RRP rule have a failure rate of between 22.5 percent and 84 percent, and WDMA says false positives have led to millions of dollars in extra costs for homeowners. Additionally, the removal of the opt-out provision more than doubled the number of homes subject to the RRP rule.