Work Safety Researching Arm Overhaul Threatens Heat Rulemaking

Layoffs at the federal agency responsible for researching work-related injuries will undercut the government’s ability to install a workplace heat stress rule, attorneys say.

Cuts to personnel at the National Institute for Occupational Safety and Health, part of the Department of Health and Human Services, will leave a range of workplace safety policies that normally spring from the agency’s research vulnerable to legal challenges claiming they’re not based in fact.

Attorneys note that OSHA’s proposed heat stress rule cited NIOSH’s criteria for a recommended standard on heat as a recognized workplace hazard and identifies control measures, like acclimatization, that companies can implement to reduce safety risks for workers.

Without the backing of NIOSH research, any heat stress regulation OSHA issues this year could be short-lived, attorneys warn.

“NIOSH was referenced throughout the proposed rule, and NIOSH’s expertise in the complex scientific issues involved in heat illness and prevention would be critical to the agency’s defense of its rule in federal court,” said Lisa B. Marsh, a principal at Jackson Lewis PC who counsels employers on workplace safety and health issues.

NIOSH, created under the Occupational Safety and Health Act, provides both the US Occupational Safety and Health Administration as well as the Mine Safety and Health Administration with research, training, and resource development for responding to on-the-job injuries and hazards.

HHS leaders notified workers April 1 that nearly 900 NIOSH staffers, almost 90% of the workforce, would be let go as part of HHS Secretary Robert F. Kennedy Jr.'s plans to cut 10,000 employees across his agency.

While lawsuits challenging those workforce cuts make their way through the courts, hundreds of NIOSH employees remain on administrative leave and are unable to work.

A federal judge paused mass firings at four different divisions within HHS last week, including the Centers for Disease Control and Prevention, where NIOSH is housed.

The rapid and conflicting changes across the courts have paused NIOSH’s work, which has downstream effects on OSHA and other agencies.

“The science-based assessments have helped employers align with OSHA expectations,” Marsh said. “Losing that expertise introduces uncertainty, especially when advising clients on risks like heat illness prevention.”

OSHA might have other options to defend a heat rule, though. Michael Felsen, a retired Department of Labor Boston regional solicitor, said there’s still evidence OSHA could pull from and experts who could support the policy.

“There are going to be lots of available experts in the field that would come forward to testify about this—I’m quite confident, if it ended up being a trial on whether this was a reasonable regulation,” he said.

Legal Ramifications

Losing NIOSH’s research means OSHA stands to lose a critical ally in defending any litigation based on general duty clause citations related to heat injury and illness under its National Emphasis Program.

OSHA uses NEPs to focus its enforcement efforts on specific hazards or industries where there’s a high risk of worker injuries. The agency conducted about 7,000 heat-related inspections and issued 60 heat citations for violations of the general duty clause between April 2022 and December 2024.

OSHA extended the NEP on outdoor and indoor heat to April 2026.

Employers often challenge those citations with success, sometimes claiming OSHA can’t regulate the hazard, and is being overly broad, according to John D. Surma, who represents employers in workplace safety and health matters.

For example, the US Occupational Safety and Health Review Commission vacated in 2013 heat stress citations issued by OSHA to the US Postal Service. The decision illustrated the difficulties OSHA faces in protecting workers from heat because the agency lacks a specific rule to address the issue.

A heat rule will be susceptible to those same legal challenges, but now OSHA wouldn’t have the subject matter experts there to support its arguments, he added.

“Unlike a private litigant, OSHA does not have the ability—in most cases—to retain private sector experts to support the rule,” said Surma. “Thus OSHA will be litigating without experts, which will create challenges.”

Nationwide Impact

The Trump administration concluded the informal hearings for the Biden-era heat proposal last week. The proposed rule has faced widespread criticism from businesses that argue it’s too prescriptive.

The administration’s decision to move forward with the hearings brings the rule closer to the finish line and comes as businesses’ and House Republicans’ receptiveness to a heat proposal has shifted.

Industries that are likely to be affected, such as construction and warehousing, are pressuring OSHA to modify the proposed heat rule to a more performance-oriented approach rather than leave it in the hands of the next Democratic administration.

“It would be harmful to workers if it’s going to be a really watered-down version,” said Felsen.

At the same time, at least 19 states notched a win last week against the Trump administration’s mass reduction-in-force plans at the HHS, which includes NIOSH, with the injunction.

However, the judge’s order doesn’t resolve the harms alleged by those states and the District of Columbia—including the sudden loss of critical services and information sharing. The injunction raised questions about what relief was gained and how the government will comply with the order.

The states sufficiently demonstrated that the HHS’s action was arbitrary and capricious, showed irreparable harm from that action, and demonstrated the negative impact it would have on the public, Melissa R. DuBose, of the US District Court for the District of Rhode Island said in granting the preliminary injunction.

“The record is completely devoid of any evidence that the Defendants have performed any research on the repercussions of issuing and executing the plans announced in the communiqué,” said DuBose.

A West Virginia federal judge ordered in May that HHS restore the jobs of all laid-off federal researchers who conduct health surveillance of coal miners, but this just saves a fraction of NIOSH so far. Most of the agency’s personnel still aren’t sure if they will return to their jobs.