OSHA’s 2026 Heat Safety Rules: What Employers Must Know to Protect Employees

As the summer heat climbs, it's time to review your company’s Heat Illness Prevention Program. In April 2026, OSHA launched a new National Emphasis Program (NEP) for Heat, expanding its reach to more indoor and outdoor sectors.

According to the U.S. Department of Labor’s Bureau of Labor Statistics, the average number of heat‑related fatalities from 2021 to 2024 was 48 per year. Most of these deaths stem from heat stroke, which occurs when the body’s core temperature reaches 104°F (40°C) or higher. Heat‑related illnesses can arise even at ambient temperatures if workers perform strenuous tasks while wearing PPE that limits heat dissipation.

When any two of the following conditions are present—high temperatures, intense activity, or restrictive PPE—employers are required to implement a comprehensive Heat Illness Prevention Program. Such a program should cover hazard identification, risk mitigation, and clear employee guidance.

Key components include:

• Regular monitoring of ambient and body temperatures.
• Frequent access to cool drinking water.
• Structured acclimatization periods for new and seasonal workers.
• Designated shaded or cooled break areas.

Studies show that 50% to 70% of outdoor heat fatalities occur within the first few days of exposure, underscoring the importance of acclimatization—gradual increase in heat exposure that allows the body to adjust.

Young and seasonal employees face a risk twice that of seasoned workers. Heat amplifies both physical strain and cognitive load, raising the likelihood of fatigue‑related accidents.

All workplace deaths and inpatient hospitalizations must be reported to your regional OSHA office. OSHA now treats heat complaints as triggers for in‑person inspections—similar to construction falls and confined‑space incidents. When a heat warning is issued by the National Weather Service, inspectors are mandated to stop and investigate sites lacking adequate water or shade.

To support this, OSHA has issued a list of high‑hazard industries for targeted, unannounced inspections. In addition to construction, landscaping, and agriculture, the list now includes package delivery, bakeries, foundries and mills, warehousing, concrete plants, and miscellaneous wholesalers.

Businesses must re‑evaluate their Heat Illness Prevention Programs in light of the April 2026 NEP. Prevention hinges on temperature monitoring, hydration, acclimatization, and cooling infrastructure—especially for vulnerable workers.

For guidance on developing a compliant program, the Illinois On‑Site Safety and Health Consultation Program offers a free, sample Heat Prevention Program. The Illinois Department of Labor provides on‑site visits, training, and even air and noise testing—an initiative funded primarily by federal grants. Learn more at https://worksafe.illinois.gov or contact Harry Hap Hileman at 217-993-2111 or harry.hileman@illinois.gov.

1. OSHA Enforcement Directive CPL 03-00-024