California study has lessons for efforts to protect workers from excessive heat : NPR

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It’s cold and snowy in much of the United States right now, but also hard to believe that in some parts of the country the warm season will eventually return, and hotter summers are increasingly a risk for American workers. This year, the federal government is considering new rules to protect employees from excessive heat. A new study examines what matters most to keep workers safe. NPR’s Alejandra Borunda reports.

ALEJANDRA BORUNDA, BYLINE: People have always known that hot weather can be dangerous for workers. Even the ancient Egyptians worried about dehydration among the people building the pyramids. And the problem is now just as critical for people working outside the home. And it’s not just heat stroke that poses a risk.

ADAM DEAN: Heat makes people slower to react and less able to make decisions.

BORUNDA: Adam Dean is a political scientist who studies labor conditions at George Washington University.

DEAN: And that means that farm workers driving a tractor or construction workers operating equipment are more likely to have a fatal accident on a hot day.

BORUNDA: Dean is the lead author of a new analysis in the journal Health Affairs. She looked at heat-related workplace deaths in California, which was the first state to adopt protections for people working outdoors. Researchers compared deaths in California with those in neighboring states that did not have these rules. The study finds that California’s rules have likely saved dozens of lives each year, even as climate change has made these heat-related risks more intense. But Dean says tweaking the rule took some trial and error.

DEAN: When California first adopted a heating standard in 2005, it was inefficient.

BORUNDA: Dean says the original guidelines weren’t specific enough. They said employers, like farmers, for example, must provide their workers with water, shade and rest in hot weather. But when inspectors showed up, they sometimes found problems, like unsafe water. The State therefore clarified. The water had to be drinkable and free, not just there, and there had to be enough shade for all workers during breaks. The state also stepped up inspections and launched an intensive campaign to educate workers about their rights. Dean says all these changes have made a real difference.

DEAN: I think a crucial lesson is that simply passing a heat standard is not enough. And it was only after the state launched a statewide crackdown that we began to see the number of deaths decline compared to neighboring states.

BORUNDA: The new study was released as the federal government is currently considering new heating rules that would apply nationally. Workers’ rights advocates want it to mimic California’s more specific rules, while many employer groups prefer a more flexible standard. The new study joins several other analyzes published this year that have found that particularly strict standards can protect workers. Barrak Alahmad is an occupational health researcher at Harvard University. He says all studies use different data sets and methods.

BARRAK ALAHMAD: And in science, you like to see that. You like to see that consistency and those extra layers of evidence.

BORUNDA: The future of federal heat rules is uncertain. They were first proposed under President Biden’s administration, and the Trump administration is currently reviewing them. Meanwhile, several states and cities have adopted their own rules in recent years, and others, like New Mexico and Arizona, are currently considering them.

Alejandra Borunda, NPR News.

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