Foryears, labor leaders have called on the federal government tocreate national regulations laying out steps employers must take tokeep workers safe when it's hot.

Last month, on a day that was sweltering even by Phoenixstandards, Filiberto Lares knew he wasn't well. An airline caterer,he said he had spent hours moving between the scalding tarmac and atruck with no air conditioning. Lares, 51, was dehydrated and fellill with a fever that would keep him out of work for four unpaiddays. It wasn't the first time this had happened.

“Honestly, I never imagined I would live a situation like thisin the United States, especially not in an industry as valued asthe airlines,” he said in Spanish.

It's a scene that plays out on airport tarmacs, in farm fieldsand on construction sites across the country: workers falling illafter laboring in hot or humid conditions for long hours withoutenough water and rest. Over the past decade, more than 350 workersnationwide have died from heat-related illness, according to datacompiled by the U.S. Bureau of Labor Statistics. Tens of thousandshave had heat-related illnesses serious enough that they missed atleast one day of work.

Related: Business, workforce will be transformed by climatechange

For years, labor leaders have called on the federal governmentto create national regulations laying out steps employers must taketo keep workers safe when it's hot. On Wednesday, U.S. Reps. JudyChu (D-Calif.) and Raúl Grijalva (D-Ariz.) introduced legislationthat for the first time would require the Occupational Safety andHealth Administration to create heat-related workplacestandards.

Currently, just three states have heat-related labor standards:California and Washington, which protect outdoor workers; andMinnesota, which protects indoor workers. California's regulations— developed more than a decade ago in response to a spate offarmworker deaths — are broadly considered the gold standard, andexperts said the state's experience is instructive in terms of whatit would take for a national law to prevent thousands of injuriesthat occur each year.

“[Heat] is not an inconvenience or a nuisance,” said MarcSchenker, a professor at the University of California-Davis whoresearches the health effects of farm work. “It's very real, withconsequences that can range from minor to fatal.”

On the federal level, heat-related stress is regulated only bythe general standard that employers must create safe workingconditions. In the absence of specific regulations, that standardis difficult to enforce. In Lares' case, he said his employer has apolicy on the books that calls for a 10-minute break every twohours when temperatures rise above 95 degrees, and that truckswithout air conditioning should not count as shade. But raisingquestions about enforcement with managers earned him onlycitations, he said, and his union had to step in to keep him frombeing fired.

The National Institute for Occupational Safety and Health, partof the Centers for Disease Control and Prevention, hasrecommendations for addressing workplaceheat stress — but no mechanism for enforcement. The principlesare fairly simple: Provide sufficient shade and rest when it's hot(what's considered hot depends on how hard the work is), as well asenough water to drink.

Because the majority of heat-related illnesses occur during thefirst few days on the job, employers should let workers acclimateand train them to spot signs of heat stress, according to therecommendations. That might have prevented the death of MiguelAngel Guzman Chavez, who died of heat stroke while picking tomatoesin Georgia last year just days after arriving in the United States.

California developed its heat standards in 2005, after 10laborers, including four farmworkers, died from excessive heatexposure in a matter of months. The legislation requires water,rest and shade for outdoor workers, as well as education. At first,the state did little to enforce the law, said Leydy Rangel, aspokeswoman for the United Farm Workers Foundation. It wasn't untilseveral more farmworkers died, including apregnant teen, and multiple lawsuits were filed that state regulators stepped upoversight, she said.

In 2015, the UFW received more than 50 complaints aboutheat-related violations and another farmworker, a father of three,died picking citrus. Complaints have steadily decreased since,though compliance remains an issue, Rangel said. Still, over thepast two years, there have been no heat-related deaths amongagricultural workers, according to state data.

Farmworker Vicente Reyes said he has seen just how much thestatewide regulations have improved working conditions. He hasworked the fields around Bakersfield since he was 11 and remembersthat people used to hide if they were feeling sick or dizzy, afraidthey would be sent away without pay. Now 19, and working and goingto college full time, he said workers are told every morning theyshould rest if they need it and reminded throughout the day. Theyalso are given shade and water.

There's still room for improvement, he said, like having betteraccess to cleaner bathrooms, but the difference is dramatic. “Youused to see people dying,” he said. “Now, they are being morecautious.”

Despite improvements in California, home to the nation's largestagricultural workforce, heat remains the leading threat tofarmworker health. Across the country, other industries are hithard as well, including construction, landscaping and postal delivery. For the population at large, heat is theleadingweather risk, causing more deaths than hurricanes, tornadoes orflooding. The threat is expected to grow as the planet warms andheat waves become more intense and less predictable.

Florida, a top seller of ferns, citrus and tomatoes, offers aprime example of the dangers. Last year, temperatures soared abovethe thresholds considered safe for very heavy labor by NIOSH onmore than 70% of days from May through September, in every Floridacounty, according to a report by Public Citizen, a nonprofit consumer advocacygroup.

In 2015, Emory University researchers did a study involvingFlorida farmworkers, who were asked to ingest small devices, thesize of a vitamin, that could track core body temperature. Theyfound that 4 in 5workers experienced body temperatures that exceeded therecommended limit of 100.4 degrees Fahrenheit on at least one ofthe three days they were monitored. And nearly 85% of the workersreported symptoms of heat-related illness, including dizziness,confusion, fainting, nausea and headaches.

“People focus on the deaths because they are so tragic anddramatic,” said Jeannie Economos, environmental health coordinatorfor the Farmworker Association of Florida and a collaborator onboth the Public Citizen and Emory University studies. “But youdon't have to just wait for somebody to die to be concerned aboutheat. The heat is so debilitating in so many other ways.”

In the absence of federal standards, some employers have beenimplementing changes on their own with dramatic results.

A decade ago, the city of Waco, Texas, wanted to do somethingabout the costly illnesses outdoor employees were experiencing dueto heat. The central Texas city regularly experiences temperaturesabove 100 degrees. Workers paving roads or grooming city parks werefalling ill, said Dr. Ronda McCarthy, city medical director at thetime.

From 2011 to 2017, McCarthy's team trained employees onprevention and screened workers for diseases such as diabetes orhypertension that might put them at increased risk for heat-relatedillness. Some people found to be susceptible had their dutiesadjusted until they got other health issues under control.

But the biggest changes came from working with managers toprovide more breaks and ensure adequate water supplies, and tostart the riskiest jobs earlier in the day when it was cooler, orswap out the hardest tasks more frequently.

By 2016, heat-related illnesses had essentially been cut to zeroand median worker compensation costs were cut in half.

In 2005, congresswoman Chu was a member of the California StateAssembly and championed the legislation that worker advocates nowhold up as a model. That legislation, combined with therecommendations from NIOSH and practices used by the military, formthe backbone of the minimum standards proposed in the new federalbill.

Public Citizen has rallied dozens of organizations in support ofthe legislation, saying climate change poses an urgent crisis foroutdoor workers.

“As temperatures continue to rise, the problem is going to getworse,” said Shanna Devine, the organization's worker health andsafety advocate. “In some places, we're going to lose the abilityto work outside.”

This KHN story first publishedon California Healthline, aservice of the California HealthCare Foundation.

Kaiser HealthNews (KHN) is a national health policy news service. It is aneditorially independent program of the Henry J. Kaiser Family Foundation whichis not affiliated with Kaiser Permanente.

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