Heat Illness Enforcement Is a Growing OSHA Liability in 2026

The Occupational Safety and Health Administration (OSHA) has been enforcing heat illness requirements through the General Duty Clause of the Occupational Safety and Health (OSH) Act since long before heat illness appeared on the agency's formal rulemaking agenda. Between April 2022 and December 2024, OSHA conducted approximately 7,000 heat-related inspections and issued 60 citations for heat hazard violations. The agency also issued nearly 1,400 hazard alert letters to facilities found to have heat-related deficiencies that did not rise to the level of a formal citation. Around 50 workers die from heat-related causes in U.S. workplaces each year. Those numbers were significant enough that OSHA revised and extended its Heat-Related Hazards National Emphasis Program (NEP) on April 10, 2026. The revised NEP runs for five years from its effective date.

The federal heat illness proposed rulemaking, published as a Notice of Proposed Rulemaking (NPRM) in August 2024, has not been finalized. Public comments closed in January 2025, informal hearings ran through mid-2025, and as of this writing no final rule has been issued. That status has not slowed enforcement. OSHA's position has been consistent: the absence of a specific standard does not remove the employer's obligation under the General Duty Clause to protect workers from recognized heat hazards. And the NEP gives inspectors a formal mechanism to conduct proactive inspections during heat events without waiting for a complaint or incident to trigger a visit.

What the General Duty Clause Actually Requires OSHA to Prove

To sustain a General Duty Clause citation, OSHA must establish four things: that a hazard existed; that the hazard was recognized, either by the employer or by the industry; that the hazard caused or was likely to cause death or serious physical harm; and that a feasible means of abatement existed that would materially reduce the hazard.

Heat is an area where the first three elements are almost always easy to establish. The existence of a heat hazard in outdoor summer work or in industrial facilities running high-temperature processes is not contestable. Industry recognition of heat as a workplace hazard is well documented. The serious harm and fatality risk is supported by decades of data. The fourth element, feasible abatement, is where General Duty Clause heat citations have sometimes been contested successfully before the Occupational Safety and Health Review Commission (OSHRC). The Commission has found in some cases that OSHA failed to demonstrate that the employer's abatement measures were materially inadequate, rather than simply imperfect.

That legal nuance matters for how EHS teams approach the documentation question. A facility with a written heat illness program, documented acclimatization procedures, supervisor training records, and field monitoring logs is in a meaningfully different position before OSHRC than one that has a written policy and nothing else. The abatement question is not just about whether the facility has protections in place. It is about whether the facility can demonstrate that those protections were actively implemented, monitored, and corrected when they failed.

State Heat Standards Have Already Gone Where the Federal Rule Has Not

While the federal rulemaking process continues, state plan states have been setting enforceable heat illness standards for years. The practical result is that employers in those states are already subject to requirements more specific than anything in the federal proposed rule, and the enforcement against those standards is active.

California's Heat Illness Prevention Standard triggers at 80 degrees Fahrenheit for outdoor work, with mandatory high-heat procedures activating at 95 degrees. California's indoor heat standard, which took effect July 23, 2024, covers most indoor workplaces where temperatures reach 82 degrees. Oregon and Washington have active heat illness standards covering outdoor work. Minnesota maintains ergonomics requirements for certain high-risk sectors. Maryland's heat illness standard, effective September 30, 2024, applies at an 80-degree Fahrenheit heat index. Nevada began enforcing its heat illness requirements on April 29, 2025. For a multi-state employer whose heat illness program was designed around general best practices rather than the specific trigger temperatures and documentation requirements in each operating state, the compliance gaps are real and they are active.

The state enforcement environments in California, Oregon, and Washington in particular are not waiting for a federal standard to establish the baseline. They already have one. EHS teams running unified programs built around federal OSHA guidance who have not mapped those programs against applicable state standards are carrying exposure they have not measured.

What OSHA Inspectors Are Actually Looking for During Heat Inspections

The NEP gives OSHA inspectors a structured framework for heat-related inspections in high-risk industries. In practice, the inspections are looking at a specific set of documentation alongside physical conditions. Inspectors check for written heat illness prevention programs, acclimatization procedures for new and returning workers, documented supervisor training, environmental monitoring records showing that temperature and heat index conditions are being tracked during heat events, evidence of adequate water access and rest breaks, and records showing that the program was actually implemented during the most recent heat events, not just described in a policy document.

That last element is the one that catches the most facilities. A written heat illness program describes what the facility intends to do. Inspection-ready documentation shows that it actually did those things during the most recent significant heat period. Environmental monitoring logs with dates and temperatures, sign-in sheets for heat illness training, supervisor field check records: those are what an inspection looks at to determine whether the written program reflects real operational practice or just a good-faith document that was never tested against an actual hot day.

The Enforcement Season Is Here and the Revised NEP Runs Through 2031

OSHA's revised NEP took effect April 10, 2026, and runs for five years from that date. It was revised based on enforcement data showing continued rates of heat-related injuries and fatalities that the agency determined justified ongoing targeted enforcement. The NEP covers outdoor and indoor work environments and applies to industries the agency has identified as high-risk for heat exposure, including construction, agriculture, manufacturing, warehousing, and logistics.

For facilities in those sectors entering the summer months, the practical implication is straightforward. Proactive inspections can and do happen during heat events regardless of whether a complaint was filed. The inspection may arrive when a heat wave hits, which is also when heat illness programs are most likely to be operating under stress. An EHS team whose program looks solid on paper but has not been field-tested against an actual heat event in the current season is working from an assumption that may not survive contact with a summer inspection.