Heat Stress at Work: OSHA, State, and City Compliance with Heat Illness Prevention Rules

For years, heat illness prevention has largely been addressed through OSHA guidance, industry best practices, and the General Duty Clause. That is rapidly changing.

In June 2026, New York City announced new heat safety requirements for city employees and contractors, directing agencies to develop and implement formal heat illness prevention plans. While this action received significant media attention, it is far from an isolated event.

Across the United States, states and local governments are increasingly implementing heat-related workplace requirements, which include heat illness prevention training for all affected workers, often without waiting for a federal OSHA standard.

A Growing Trend

Employers should take notice. Heat illness prevention is rapidly becoming one of the fastest-growing areas of occupational safety regulation in the United States. New requirements are appearing at the state level, while municipalities are increasingly focusing on occupational heat exposure for public employees and city contractors.

Where Occupational Heat Exposure Requirements Exist or Are Being Developed

Note: The information below is current as of June 2026. Because legislation, rulemaking, and municipal policy initiatives continue to evolve, employers should verify the latest requirements applicable to their jurisdiction.

California

California maintains one of the nation’s most comprehensive heat illness prevention programs. Employers with outdoor workers must provide drinking water, access to shade, training, emergency response procedures, and acclimatization measures. California has also adopted an indoor heat illness standard applicable to many indoor workplaces.

Oregon

Oregon’s heat illness prevention rule requires employers to implement protections when temperatures reach specified thresholds. Requirements include drinking water, rest periods, shade or cool-down areas, employee training, and high-heat procedures during extreme conditions.

Washington

Washington’s outdoor heat exposure standard requires training, drinking water, and preventive measures based on temperature thresholds and work conditions, including protective clothing and exposure duration.

Nevada

Nevada requires employers with more than ten employees to maintain a written job-specific heat illness prevention plan, provide employee training, and implement measures to reduce occupational heat exposure.

Maryland

Effective September 30, 2024, Maryland’s heat stress standard applies to both indoor and outdoor workplaces when the heat index reaches 80°F. Employers must implement heat illness prevention procedures, employee training, monitoring, and emergency response measures.

Minnesota

Minnesota’s occupational safety framework includes protections addressing excessive indoor heat exposure and employer responsibilities to mitigate heat hazards.

Colorado

Colorado has implemented heat-related protections primarily affecting agricultural workers and continues to evaluate expanded occupational heat exposure requirements.

In addition, Illinois & Arizona are both in the midst of the rulemaking process to propose permanent heat illness prevention regulations at this time.

Municipal Occupational Heat Exposure Requirements (City-Level Programs)

While most enforceable heat standards are being developed at the state level, several cities have implemented occupational heat exposure requirements for city employees and/or city contractors.

New York City

In June 2026, New York City directed city agencies to develop heat illness prevention plans for municipal employees and contractors. The initiative includes occupational heat hazard assessments, employee training, preventive work practices, and emergency response procedures designed to reduce heat-related illness during extreme conditions.

Phoenix, Arizona

Phoenix has implemented one of the most comprehensive municipal heat response and occupational heat mitigation frameworks in the country. While much of its system is focused on public safety and emergency response, the city also applies occupational heat exposure controls for city workers and certain contractors, including hydration requirements, shade provisions, rest breaks, training expectations, and heat safety planning on covered projects.

Los Angeles, California

Los Angeles aligns closely with California’s statewide heat illness prevention requirements and applies additional occupational heat safety expectations for city operations and contracted work, including heat emergency response planning and worker protection measures during high-heat conditions.

Las Vegas / Clark County, Nevada

Local government entities in the Las Vegas area support occupational heat safety through public employer policies and contractor expectations that align with Nevada’s statewide heat illness prevention requirements.

Other Municipalities

Additional cities, particularly in the Southwest and Sun Belt regions, have implemented occupational heat exposure policies primarily through:

• Public works safety programs
• City contractor requirements
• Emergency heat response protocols
• Cooling and hydration infrastructure for workers

While these municipal initiatives vary in scope, they generally focus on public employees and contracted work rather than broad private-sector regulation.

Federal OSHA Is Still Moving Forward — and Enforcement Is Already Active

Meanwhile, federal OSHA continues advancing its Heat Injury and Illness Prevention rulemaking process, with a proposed nationwide standard still under development. While the final rule has not yet been issued, employers should not interpret this delay as reduced regulatory attention.

In fact, OSHA has already made heat illness prevention a current enforcement priority.

Under OSHA’s existing enforcement framework, including the General Duty Clause and ongoing national enforcement initiatives, employers are already being cited when workers are exposed to recognized heat hazards without adequate protective measures in place.

⚠️ Important Enforcement Note: OSHA Heat Focus Program

Employers should also be aware that OSHA has implemented a Heat Illness National Emphasis Program (NEP), which directs compliance officers to proactively target and inspect workplaces where employees are exposed to hazardous heat conditions.

This means:

• Heat-related inspections are increasing across high-risk industries
• Outdoor worksites (construction, agriculture, utilities, landscaping, transportation) are being actively targeted
• Indoor heat hazards (warehousing, foundries, manufacturing, kitchens, and non-air-conditioned facilities) are also within scope
• OSHA is evaluating whether employers have implemented basic heat illness prevention measures even in the absence of a specific heat standard

In practical terms, this significantly raises the enforcement risk profile for employers who have not implemented a structured heat illness prevention program.

Key Takeaway for Employers

Even without a final federal heat standard in place, OSHA is already treating heat exposure as a known, preventable workplace hazard. Employers should expect that heat-related incidents—especially those involving hospitalization or fatalities—may trigger immediate federal inspection activity under the NEP and General Duty Clause.

Waiting for a final rule is no longer a defensible strategy. Organizations that proactively implement heat illness prevention programs now are far better positioned to reduce both employee risk and regulatory exposure.

What Employers Should Be Doing Now

Regardless of your location, every employer with outdoor workers—or employees working in hot indoor environments—should consider implementing a comprehensive heat illness prevention program that includes:

• Employee training
• Acclimatization procedures
• Access to drinking water
• Rest breaks
• Shade or cooling areas
• Emergency response procedures
• Supervisor training
• Heat illness reporting procedures

These are increasingly becoming the expected elements of a defensible heat illness prevention program.

Heat Illness Prevention Training Is One of the Simplest Ways to Reduce Risk – And It’s Required

Training employees and supervisors to recognize the signs and symptoms of heat-related illnesses can significantly reduce the likelihood of serious incidents.

Our online Heat Stress Prevention Training courses for workers and supervisors  make it easy for employers to train affected employees, document participation, and demonstrate a proactive commitment to employee safety.

Available Courses:

Heat Stress Prevention Training (Initial Training)

Our initial heat illness prevention training course covers:

• Causes of heat-related illnesses
• Risk factors and contributing conditions
• Heat exhaustion, heat stroke, heat cramps, and heat rash
• Recognition of warning signs and symptoms
• Prevention strategies
• Acclimatization practices
• Emergency response procedures
• Employee responsibilities

A certificate of completion is provided upon successful course completion.

Heat Stress Prevention Refresher Training

Our refresher course for heat illness prevention is ideal for annual training and reinforcement of critical concepts, including:

• Recognition of heat-related illnesses
• Prevention measures
• Emergency response procedures
• Employee and supervisor responsibilities

A certificate of completion is provided upon successful course completion.

Whether your employees work in construction, manufacturing, warehousing, oil and gas, transportation, agriculture, landscaping, utilities, or other high-heat environments, effective training is one of the most cost-effective ways to reduce risk and support compliance efforts.

The Bottom Line

Heat illness prevention is no longer simply a recommended best practice. Increasingly, it is becoming an expected component of workplace safety programs across the country.

As more states and municipalities adopt heat-related occupational exposure requirements, employers who proactively implement training and prevention measures today will be better positioned to protect their employees, reduce liability exposure, and avoid costly citations tomorrow.

If your organization needs employee heat stress training, our online Heat Stress Prevention Training and Heat Stress Prevention Refresher courses provide a convenient, affordable solution that can be completed anytime, anywhere.

Don’t wait for a heat-related incident or a new regulation to take action. Start building a stronger heat illness prevention program today.