Extreme heat is the number-one weather-related killer in the U.S., causing hundreds to thousands of deaths every year. And available estimates are assuredly undercounts because heat is not always accounted for on death certificates. The need to protect people is becoming clearer and more urgent as heat waves happen more often, last longer and become hotter with climate change.

Fully dealing with the threat would mean tackling systemic issues, from mitigating climate change to rectifying inequities in who is exposed to heat and can afford to cool themselves off. But there are also common-sense protections that could—and should—be put in place by both businesses and our government to prevent heat illnesses and deaths. These changes make economic sense, but more important, they are the humane thing to do.

If we want people to do their jobs optimally, we should give them the protection they need to do so.

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Extreme heat can cause heat exhaustion (characterized by nausea, dizziness and muscle cramps), heatstroke (an elevated core body temperature, often higher than 104 degrees Fahrenheit, which can damage organs if not promptly treated), and even death. Older people, those with certain health conditions or taking certain medications, and outdoor workers are particularly at risk of heat illness. Outdoor laborers can be especially vulnerable because, in addition to the danger posed by the ambient heat, their work often raises their body temperature.

The U.S. Bureau of Labor Statistics documented 34 heat-related deaths of workers per year between 1992 and 2022, as well as an annual average of 3,389 injuries and illnesses that caused people to miss days of work between 2011 and 2022. And an examination of workers’ compensation claims in California that included more cases than just those where people missed work found three to six times the number of illnesses and injuries compared with the Labor Bureau’s records for that state.

A few states, such as California and Oregon, have enacted protections for workers following the rubric of “water, rest, shade”—workers should have ready access to drinkable water and ample rest breaks, ideally in air conditioning and at least in shade, to allow the body to cool and recover. The physiological science behind these interventions is clear, and formal protections requiring these measures have worked.

As with many rules proposed late in the Biden administration, its fate depends on the Trump administration’s willingness to put the safety of the American population first.

But piecemeal state legislation leaves many workers unprotected. Scientists and policymakers have argued for a federal standard set by the Occupational Safety and Health Administration (OSHA) since the agency’s inception in the 1970s. In 2024 OSHA finally proposed a rule that would require not only access to water, rest breaks, and shade or other cooling areas but also heat safety training and protocols to acclimatize new and returning workers to high-heat conditions. As with many rules proposed late in the Biden administration, its fate depends on the Trump administration’s willingness to put the safety of the American population first.

The current administration should see this rule through—and maintain robust OSHA staffing to enforce it—because it would not only avert highly preventable deaths but also improve economic productivity. Research shows that unrelieved exposure to high heat impairs concentration, coordination and decision-making. If we want people to do their jobs optimally, we should give them the protection they need to do so.

Some businesses have opposed heat health rules, arguing that they impose expenses and that people should be responsible for themselves—an Oregon farm company made this argument after the death of one of its workers before the state enacted its heat safety law. But most of these measures are relatively inexpensive. In addition, heat illness is notoriously difficult for anyone to recognize in themselves, and as a vulnerable class, laborers sometimes avoid taking voluntary breaks for rest or water because they believe doing so will make their bosses think they aren’t hard workers and might cost them their jobs.

Existing state rules and the proposed OSHA standard give businesses flexibility in implementing protections: farms may need to have mobile hydration and cooling stations, whereas an oil and gas facility might be able to erect permanent shaded areas for its workers. The goal is to keep people safe, not to impose rigid burdens on businesses.

For these reasons, it would actually be in the economic interest of companies, especially ones that operate in multiple states, to lobby the administration to maintain the rule so they can avoid the patchwork of requirements across the country (although states would still be allowed to institute stricter rules on their own).

In 2015 California strengthened its rules about worker protection and saw positive changes. Part of this success was the result of better enforcement. That is another reason to put an OSHA heat safety standard in place: a specific standard would greatly simplify enforcement. Under a current rule known as the General Duty Clause, the agency must go employer by employer and meet a list of criteria to enforce action.

If the Trump administration does not keep the federal rule, states must be ready to step into the breach to protect workers. They need not reinvent the wheel—the proposed OSHA rule, as well as regulations passed in states such as California and Oregon, could be readily adapted to other places.

Further, states such as Texas and Florida that have passed laws banning local jurisdictions from enacting heat safety regulations must reverse course. Texas and the Southeast have seen some of the largest increases in the number of days when heat and humidity rise to dangerous levels, meaning workers in those states are protected only if they are fortunate enough to work for a company that voluntarily provides adequate safety measures. Protecting people, not just businesses, is the government’s job.

Providing access to very basic cooling measures is an overall inexpensive way to keep people safe and has the side benefit of economic efficiency. As Sharon Block, a Harvard Law School professor and labor lawyer, puts it, “it’s not just the decent thing to do but the smart thing to do.”