Last year, 2024, was the hottest year on record nationally and in 17 states. According to the National Climate Assessment, as warming continues, it is likely that heat waves will become more intense and more frequent. Given the current risks, and the expectation of growing extreme heat events exacerbated by the effects of climate change, heat is a serious and growing environmental and occupational health hazard that state leaders cannot ignore.
Heat-related illness has been recognized as an occupational hazard for decades. Working in extreme heat conditions poses significant risks of heat-related illness for indoor and outdoor workers, including heat exhaustion and heat stroke; occupational injuries such as burns and falls; exacerbation of preexisting conditions, such as asthma, kidney disease, and heart disease; and premature death. Even with the likelihood of significant undercounting, the U.S. Bureau of Labor Statistics (BLS) estimates there were 33,890 work-related heat illnesses and injuries that required days away from work from 2011 to 2020, as well as nearly 1,000 worker deaths from heat exposure from 1992 to 2021.
The health consequences of extreme heat lead to a number of economic losses, including lost worker productivity, increased health care costs, and increased worker compensation claims, along with threats to workers’ financial stability when heat-related illnesses necessitate work absences.
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As extreme heat conditions become more frequent and more hazardous, and as the Trump administration is unlikely to provide federal extreme heat protections, it is essential that states adopt and replicate successful models that establish and improve state rules or standards to protect workers from extreme heat. This column compares existing state extreme-heat worker protections (see Table 1) and recommends measures for how to enhance them.
Federal OSHA standards vs. OSHA-approved state plans
The Occupational Safety and Health Administration (OSHA) sets and enforces federal workplace safety and health standards that apply to most of the federal and private sector and most state and local employees. State plans are required to be at least as effective as the federal Occupational Safety and Health Act at protecting workers and preventing work-related injuries, illnesses, and deaths. Twenty-nine states administer their own OSHA-approved and monitored workplace safety and health plans, which offer stronger protections than the floor set by federal standards. Twenty-two state plans cover both private sector and state and local government workers, while seven cover only state and local government workers.
Although the Occupational Safety and Health Act requires employers to provide working conditions that are free of known hazards likely to cause serious physical harm or death, there is no specific federal law that protects workers in America from extreme heat. Without a consistent federal standard for determining what constitutes a serious heat hazard, regulators face enforcement challenges because they must meet a higher burden of proof to claim heat as the cause of injury or death.
In 2024, the Biden administration proposed a federal rule that would have filled this gap. The rule would have saved the lives of both outdoor and indoor workers, many of whom face health and safety risks from extreme heat due to a lack of or inadequate access to cooling mechanisms such as shade, water, and air conditioning. However, it is unlikely that the Trump administration will finalize this rule. The first Trump administration paused OSHA’s efforts to finalize many health regulations, and the current administration has already gutted the National Institute for Occupational Safety and Health (NIOSH). NIOSH developed the “Criteria for a Recommended Standard: Occupational Exposure to Heat and Hot Environments,” the basis for the Biden administration’s draft rule, which contains recommended strategies for heat measurement and mitigation based on evaluation of scientific data on heat stress and hot environments.
With the improbability that a new federal heat protection will come to fruition, as well as the increase in extreme heat conditions, it is particularly important for states to protect their workers by developing standards if they don’t have them or strengthening their current standards to account for increasing extreme heat conditions.
State plans with heat-specific worker protections have been enacted in California (for both indoor and outdoor workers), Colorado, Maryland, Minnesota, Nevada, Oregon, and Washington state. These protections vary in scope, covering certain workers in specific settings in varying ways. Table 1 provides an overview of existing state standards to protect workers exposed to extreme heat.
Recommendations for state policies to protect workers from extreme heat
State policymakers have several tools at their disposal to advance policies that protect workers from extreme heat. If states don’t have specific heat standards, policymakers can develop them. For instance, extreme heat worker protections are under consideration in Arizona, Massachusetts, New Jersey, New Mexico, New York, and Rhode Island. Florida lawmakers introduced protections for outdoor workers in 2024 after a Tampa Bay Times investigation found that from 2013 through 2023, twice as many workers in the state had died from heat than previously had been reported to OSHA.
Local authorities also can enact standards to protect workers, such as the Phoenix ordinance that requires protections for all city contractors and subcontractors. However, their authority to do so can be blocked by state preemption laws; Florida and Texas have passed legislation that prohibits localities from creating heat protections not offered by the state.
Finally, industry-specific laws may be practical for states that do not have their own OSHA plans; for instance, laws can mirror statewide or federal policies that offer some protections to construction workers or warehouse workers.
Policymakers don’t have to start from scratch. Current state policies and the Biden administration’s draft heat standard provide guidance for adopting or adapting occupational heat standards and can strengthen protections for outdoor and indoor workers. Below are provisions that state leaders should consider as they take steps to advance policies that protect workers, as recommended in a Center for American Progress comment letter to OSHA regarding the draft heat standard.
1. Injury and illness prevention plans for both indoor and outdoor workers
Heat standards should require that employers develop and implement a written worksite heat injury prevention plan (HIIP) to address heat hazards for both outdoor and indoor workers. HIIPs should include, at a minimum, procedures for providing drinking water, shade, preventive rest periods, close observation while workers are acclimatizing to heat, high-heat procedures, training, and prompt emergency responses. Plans should prioritize worker safety over short-term cost savings and acknowledge that the long-term costs of heat-related injuries significantly outweigh the costs of compliance.
2. Identification of heat hazards using WetBulb Globe Temperature
Heat standards should link heat triggers to the National Weather Service WetBulb Globe Temperature (WBGT). Unlike the heat index, which includes only temperature and humidity and is measured in the shade, WBGT takes into account not only temperature and humidity but also wind speed and sun exposure, including solar radiation, in calculating heat.
Employers should respond to rising temperatures based on actual heat measurements on-site throughout the day, as opposed to estimates or forecasts from websites or weather stations, since heat fluctuates and is dependent on factors such as ground surface composition.
3. Acclimatization periods to protect new and returning workers
Heat standards should mandate employers to follow the 20 percent rule of gradually increasing workload and heat exposure to build workers’ heat tolerance. The 20 percent rule recommends that employers begin with 20 percent exposure on the first day, increasing by no more than 20 percent each following day, until full acclimatization is reached over the course of two weeks.
Acclimatization periods are critically important to protect new and returning indoor and outdoor workers from hazardous heat, as they allow the body to build tolerance to working in the heat. Employers should be required to ensure that all new employees and any employees returning to work after being away for more than two weeks follow acclimatization procedures for the first week of work.
4. Mandatory paid rest breaks
Heat standards should include paid rest breaks to ensure that workers’ health is consistently safeguarded. This would align with fair labor standards that require compensation for safety procedures critical to core job duties, such as putting on and taking off protective gear. Employers should require employees to take frequent and longer rest breaks as heat conditions increase.
Heat safety plans and worker training materials should clearly emphasize that workers have the right to take rest breaks and that employers must support them in doing so, particularly as temperatures rise.
5. Training and language-accessible training materials
Heat standards should require employers to ensure effective training for employees in the following areas:
- Environmental and personal risk factors for heat illness
- Employers’ procedures for responding to signs of possible heat illness and for complying with the standards’ requirements
- The importance of drinking water during shifts
- The concept, importance, and methods of acclimatization
- The different types and common signs of heat illness
- Appropriate first aid and emergency response in the event of heat illness, as well as employers’ procedures for contacting emergency medical services
- The importance of employees reporting symptoms or signs of heat illness in themselves and others
Heat standards also should ensure that all training materials are accessible in the languages that workers speak. Studies have shown that failure to account for language barriers can lead to workers not understanding critical safety protocols. Employers should make efforts to identify and address the specific languages present among their workforces.
6. Assessment and control measures, including monitoring heat risk using a buddy system
Heat standards should require employers to monitor for signs and symptoms of heat-related illness. They should implement a formal buddy system in which employees monitor each other for signs and symptoms of heat-related risks.
7. Emergency response procedures
Treatment for heat stroke includes restoring normal body temperature within 30 minutes of collapse to avoid cell damage. Heat standards should require that supervisors use effective, accessible means of communication with workers at all times; that employers monitor and provide care to employees exhibiting symptoms of heat-related illness; that on-site first aid materials are easily accessible; and that worksites can easily accommodate emergency medical services and responders. Heat standards should also require the use of effective whole-body cooling equipment such as cold-water immersion tubs and tarps with ice and water to reduce body temperature during an emergency.
Conclusion
In 2021, the U.S. agriculture, construction, manufacturing, and service sectors lost more than 2.5 billion hours of labor due to heat exposure. Heat-induced declines in labor productivity are rising as extreme heat worsens, currently averaging $100 billion annually in the United States, with the potential to reach $200 billion within the next five years and $500 billion by 2050.
Without federal heat protections in place, states should make sure they are protecting workers by implementing standards if they have not yet done so and by identifying opportunities to strengthen protections that they already have in place. Heat standards should include provisions that require employers to implement effective heat prevention plans; monitor and correct for extreme heat exposures; educate workers about extreme heat dangers and ways to protect themselves; establish emergency response procedures; and use preventive measures such as paid rest breaks, water, and shade for employees working in hot conditions.
Such actions would protect the health and well-being of workers, enhance worker productivity, and reduce the economic damages incurred from exposing unprotected workers to the rising dangers of extreme heat.
The authors would like to thank Akshay Thyagarajan for his assistance with fact-checking.