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Outdoor workers could be exposed to even more days of extreme heat, report finds

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Francisco Rafael Ruíz Soto had been working for six hours straight one Friday, patching the roof of a two-story house near Mount Lemmon near Tucson. The summer sun had pushed temperatures to about 109 degrees, Ruiz Soto estimated. His boss, who was working with him that day, had provided water, but it had been sitting out in the heat.  

Ruíz Soto, 43, works with the Southside Worker Center, which offers short-term jobs. The center allows workers to turn down work depending on the pay and other factors.  

That means Ruíz Soto’s boss is different most days, he said, speaking in Spanish. Sometimes, they don’t offer water, so he started carrying an ice chest filled with cool water and electrolyte drinks. Most summer days, he drinks about 20 liters of water. 

He still got sick that day. Ruíz Soto spent the weekend with a headache and a 101.3-degree fever. His boss fared worse, he said, with cramping in addition to a fever. Neither went to the hospital. In the five years Ruíz Soto had been in Arizona, he said he has experienced heat related illness one to two days each summer.

A new report now warns that outdoor workers like Ruíz Soto might be exposed to even more days of extreme heat as temperatures continue to rise.

The report, called “Too Hot to Work” from the Union of Concerned Scientists (UCS), a science advocacy group, says that if no action is taken to reduce greenhouse gas emissions by 2050, outdoor workers’ exposure to days with a heat index (or “feels like” temperature) over 100 degrees will quadruple.  

In Arizona, outdoor workers make up 22 percent of the total workforce, according to the report. Outdoor workers include construction workers and electricians, farmers and landscapers, police officers and truck drivers. The report also warns that Latino and Black communities are overrepresented in outdoor work and would experience an outsize impact. 

Kristina Dahl, a senior climate scientist at UCS and one of the report’s authors, said the group chose to focus on outdoor workers because of their particular vulnerability. Outdoor workers in the U.S. have up to 35 times the risk of dying from heat exposure compared with the general population, a study from 2015 found. 

Outdoor workers “are essential to the functioning of our society — they are people who make the food that lands on your plate at dinner, they're the people delivering our packages, fixing the roads and bridges in our hometowns,” Dahl said. “And yet the work they do is fairly invisible, and they're often doing that work despite above-average risks and below-average pay.” 

The risks appear likely to grow. A United Nations report released Aug. 9 found that certain effects of climate change, including severe heat waves and droughts, are “locked in” and will continue to worsen for at least 30 more years, even if quick action is taken to reduce greenhouse gas emissions.  

And researchers continue to find signs that climate change will affect certain communities more than others. A September report released by the Environmental Protection Agency tested how vulnerable groups would fare with climate change and found that Latino, Black and Native American communities in particular are more likely to live in areas that climate change will impact the most.  

Now, some advocates and workers wonder, as climate change makes days hotter, and more days hot, what will happen to workers who have to deal with the heat? 

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The heat is bad today, but it could get worse

Working in extreme heat has already altered lifestyles for many.  

Anthaniel Long, 24, who works as an electrician in Tempe, doesn’t drink anything with caffeine during the hot summer months. He drinks two gallons or more of water each day, uses ice packs after work if he’s sore and tries to stay away from sugar. Long spends about a quarter of his week outdoors, and he's conscious about staying hydrated. 

His company, DP Electric, treats him and other workers well, he said, providing them with water, ice and access to cool-down stations. Still, there’s no avoiding some effects of working outdoors in the heat.  

“With the heat, you deal with a lot more symptoms. It's the heat sickness, you get cramping,” he said. “It's definitely a recovery and go-again kind of regimen.” 

Other workers, like Antonio Piñeda, said their health has suffered directly from working in the heat. 

Speaking at an event called Arizona’s Workplace Heat Crisis Speakout, organized by a coalition of advocacy groups, Piñeda said he was working for three hours on a roof in 2019 when the temperature was 109 degrees outside. He started feeling dizzy. As he drove home that day, he had to stop every 10 minutes because he couldn’t move his arms.  

As Piñeda recounted his story, he teared up. He said he started thinking about how he was risking his life for “some money that’s going to last one day.” The heat affects his mental health too, he said.  

The UCS report found that if no action is taken to reduce heat-trapping emissions, the number of days workers are exposed to a heat index over 100 degrees would quadruple. If “slow action” is taken, workers would be exposed to triple the days. 

The authors describe a “no action” scenario as heat-trapping emissions rising through the end of the century. The “slow action” scenario describes heat-trapping emissions increasing only until the middle of the century, and then declining after that.  

Counties projected to have the highest number of workers exposed to extreme heat include those encompassing Chicago, Houston, Miami and Phoenix.  

Extreme heat affects Latino and Black communities in particular, whose members are represented in outdoor work at disproportionate rates. While Latino people make up 17 percent of the general population, they are nearly 30 percent of outdoor workers. Black people are about 13 percent of the population, but 14 percent of outdoor workers. 

A separate study from the Atlantic Council underscored the risks and the inequity of climate change for workers. It found that fatalities due to extreme heat could rise from 8,500 deaths in a current year to almost 60,000 deaths by 2050, with increases projected in Arizona, Southern California and southwest Texas in particular. Occupational injuries, which are currently about 120,000 per year, could rise to 450,000 by 2050 if no action is taken on climate change. 

"These numbers represent a red-hot call to action, and without significant change, we will further melt the U.S. economy and take American workers down with it," said Kathy Baughman McLeod, who is the director of the Adrienne-Arsht Rockefeller Foundation Resilience Center at the Atlantic Council. "Not surprisingly, those least responsible for rising temperatures are being dealt the biggest blow from them."

Extreme heat: Few resources, long distances make heat deadlier in rural Arizona

Will worker earnings be at risk? 

The UCS report also puts a cost to the rising temperatures, estimating that $55 billion in worker earnings could be at risk by midcentury if no action is taken to curb emissions.  

But that's assuming employers follow recommendations for outdoor workers from the Centers for Disease Control and Prevention, which suggests reducing moderate physical work when the combination of heat and humidity exceeds 100 degrees. Many employers and workers aren’t even aware of these recommendations, which aren’t easily accessible on the CDC’s website. 

If the recommendations were well known, several workers The Arizona Republic spoke with said it’s unlikely they would take time off from work because of the heat.  

In the past three decades, an average of 111 days a year were over 100 degrees in Phoenix, and even more in Yuma, where many agriculture jobs are located. If Arizona workers followed the CDC’s recommendations, they could have to take time off for 30% or more of the year.  

“Taking days off in the trade is definitely tough, we’re going to work to go get our check,” Long said. “So it would definitely affect me.” 

Long added that taking days off has implications for other crews on a construction site.  

"I take days off when I know I need to, personally,” Long said. “But taking days off on a job site definitely affects other people's jobs too. So if all the electricians took days off, it affects everyone else … because we work on a schedule for buildings and if those schedules aren't met at certain time periods, certain crews can't work, you know what I mean? So it's a chain event.” 

Extreme heat still has economic consequences. Time off from heat-related illness could cost employers, and productivity decreases when working outside becomes hard to manage. 

“What I learned in the heat is I don't push myself as hard as I usually would,” said Brennan Hunt, a brick tender who moved to Phoenix from Illinois two years ago. “We usually go full stop. Now it's kind of more of you going, but you’re not going to overexert yourself, so you won’t be exhausted by the end of the day.” 

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What are protections like? 

The federal agency in charge of protecting worker safety is the Occupational Safety and Health Administration (OSHA). But some states have opted to administer U.S. safety laws and regulations through their own agencies.  

Arizona’s state plan, which is administered by the Arizona Division of Occupational Safety and Health (ADOSH), does not specify a temperature that is too hot to work outside. Most days during Arizona summers reach a 100-degree heat index, the temperature at which the CDC recommends a decrease in work.  

ADOSH instead uses a “general duty” clause, which all states have to follow if there are no specific standards in place. The clause states that employers must provide a workplace free of hazards that could lead to death or serious physical harm. If they violate that clause, ADOSH can issue citations that come with a financial penalty that can reach thousands of dollars, said Jesse Atencio, the director of ADOSH.  

When a worker reports a complaint to OSHA or ADOSH, the agency will determine if it's a valid concern and then decide whether to do an inspection or informal investigation, according to Zachary Barnett, who is the area director for OSHA’s Phoenix office. In an informal investigation, the agency will contact the employer, let them know they’re aware of a situation and ask for a response.  

“There's discretion on our part about how we respond,” he said. “Sometimes people, frankly, complain about user comfort. An example would be someone who's working in an office, and it's 95 degrees in here, and the AC’s shut off. Well, that's an uncomfortable environment. But the ones that concern us most are ones we really think people can get sick or injured, and often those are people working outside, particularly with the temperatures and weather we have here in Arizona.” 

Barnett said he frequently hears about someone who suffers heat-related illness after they’ve developed it, particularly if they’re hospitalized. Employers are required to report all incidents where their employees have been hospitalized and received treatment for something more than first aid.  

Heat-related illness is a common reason why people go to the emergency department and it’s not uncommon for people to die from it, according to Frank LoVecchio, an emergency room doctor at Valleywise Health Medical Center and medical director of clinical research at Arizona State University College of Health Solutions. 

“I don’t know if you can ever totally get used to working in 120-degree weather or 110-degree weather,” he said. “You have to know how to take breaks, hang out in the shade, drink lots of water, more so than most people are used to. But we do see quite a bit of workers. A common field is landscapers, unfortunately, a lot of landscapers came in last year.” 

Some advocates think the number of workers injured from heat-related illness is undercounted. 

LoVecchio said workers often come into the emergency department in an altered state, sometimes even unconscious. That makes it hard to understand their health history and the incident that brought them to the emergency room. It could also help contribute to an undercount of heat-related deaths and injuries that occur while working.  

Peter Dooley, an industrial hygienist and safety consultant with the National Council for Occupational Safety and Health, said he thinks some of ADOSH’s investigations might not be as complete as they should be. 

“The description of the workplace fatality indicates to me that there should be citations and fines issued, from what I can read from the descriptions that are publicly available,” he said. “It doesn't add up, from what I know as a health and safety professional.” 

It’s unclear how many workers are aware that they can report heat related illness to ADOSH. Ruíz Soto said he was unaware that he could report his incident.  

Hunt thinks that most workers probably wouldn’t report an incident, even if they were aware they could. 

"They probably would not report it … if somebody has heatstroke, they report it to the company, they probably take a day or two off, and they'd be back at work,” he said. “It’s a money thing. I don't think people are going to risk not getting a paycheck or getting a short paycheck, because the job’s not going to pay you. If you don't have any sick time, they're not going to pay you because you got sick out there.” 

Extreme heat: Low-income and Latino neighborhoods suffer more in the Southwest, study shows

The bill worker advocates are fighting for 

Several advocates, including the UCS report’s authors, are pushing for a piece of legislation called the Asunción Valdivia Heat Illness and Fatality Prevention Act. The bill, which is making its way through both the U.S. House and Senate, has been popular with worker advocacy groups for a long time.  

It’s named after a California farmworker who died in 2004 from heatstroke after picking grapes for 10 hours straight in 105-degree weather. The bill would require the Labor secretary to create mandatory heat standards for workers enforceable by OSHA.

What many advocates like about the bill is that it puts a timeline on such standards — 42 months — whereas some fear a federal workplace standard pursued the usual route could take up to eight years.  

"Standards provide this sort of play-by-play guidebook of what folks need, including ... whistleblower protections,” said Dr. Teni Adewumi-Gunn, a science fellow at the Natural Resources Defense Council. “So if a worker does come out and say, this particular workplace is egregious, that their rights are protected to do that, they're protected from retaliation from employers.” 

The authors also want the heat standard to take into account factors like air pollution, the urban heat island effect and exposure to toxic pesticides, which also influence working conditions.  

A similar bill to the Asunción Valdivia Act was introduced in Arizona. The measure, House Bill 2684, tried to create heat protective standards for Arizona’s outdoor and indoor workers. It died without a vote.  

Piñeda said that while his bosses usually give him water, workers need more than that.

“They’re not exposed,” he said. “They don’t feel what we feel.”  

He wants the government to make employers offer rest time — for every two hours of work, workers would get a 10-minute break with water and shade. 

Hunt, the brick tender, said he would prefer a cutoff, where if the heat index reached a certain point, employers would be forced to cancel work, even if that means he misses a paycheck. He said his bosses in Illinois would stop work at minus 17 degrees during cold weather, but in Arizona, he has worked at 120-degree temperatures.  

In Arizona, many employers have shifted worker hours during the summer. They might work from around 5 a.m. to 1 p.m. to avoid the hottest part of the day.  

“If you expect to see construction workers, and I'm talking a lot of your large buildings, a lot of the large contracts, if you're expecting to see construction workers out there, the full crews, I'm talking framers, roofers, if you expect to see them after 2 o’clock, you got another thing coming,” said Atencio, the ADOSH director. “They start work earlier in the summer months. And a lot of employers in the state do that, because they know they don't want their employees who have to work outdoors to be experiencing the hottest part of the day.” 

Dahl, the climate scientist, said she considered how a shift in working hours to cooler times of day would affect worker safety. While it can be “very effective,” night shifts are also associated with higher risk of Type 2 diabetes and depression. 

“It's easy to think, ‘Oh, we could just shift work to nighttime and everything would be fine,'” she said. “But there are repercussions for the health of workers with that type of work as well.” 

Zayna Syed is an environmental reporter for The Arizona Republic/azcentral. Follow her reporting on Twitter at @zaynasyed_ and send tips or other information about stories to

Environmental coverage on and in The Arizona Republic is supported by a grant from the Nina Mason Pulliam Charitable Trust. Follow The Republic environmental reporting team at and @azcenvironment on Facebook, Twitter and Instagram.