Kevin Morris, a construction supervisor in Columbia, was working with his crew on a new gas station in early September as temperatures reached 94 degrees and a heat warning was in effect.
Morris said the combination of heat and humidity makes long workdays physically and mentally exhausting.
“This summer has been miserable," Morris said. "It's hot. It just feels worse than what it normally gets. The dry heat is tolerable. But the humidity and the wind — it's not a breeze, it's just blowing hot air against you. So there's no escaping it.”
For Morris, the hardest part of the day comes after noon.
“It's OK till about noon and then it gets just worse and it just drains you physically and mentally.”
His employer provides workers with water, shade and breaks. But Morris said workers still have to monitor themselves for signs of heat illness.
“You just got to keep track of things because you do not want to have a heat stroke ever. Because once you have one of those, you have them all the time.”
About one-third of U.S. workers regularly work outdoors as part of their jobs, according to the U.S. Bureau of Labor Statistics.
As temperatures rise, those workers face greater risks from heat-related illness. But Missouri does not have a state-specific workplace heat standard, leaving workers largely dependent on federal regulations and employer-provided protections.
At the same time, the federal government is changing how it approaches workplace heat safety.
Federal heat protections are changing
The Occupational Safety and Health Administration, or OSHA, has been changing its approach to workplace heat safety.
In April, the agency issued a revised National Emphasis Program for Heat. The program was originally launched during the Biden administration in 2022 to increase inspections in industries where workers face a high risk of heat exposure.
The original program directed each OSHA regional office to double the number of on-site inspections from its 2017-2022 baseline. The Trump-era revisions remove that target and do not establish another numerical inspection goal.
Currently, OSHA is also reviewing another Biden-era proposed federal heat standard that would require employers to take steps such as providing water, rest breaks and other protections for workers exposed to extreme heat.
The agency is considering changes that would make the proposed rule less restrictive.
Travis Parsons, director of occupational safety and health with the Laborers’ Health & Safety Fund of North America, said the proposed changes could shift OSHA’s focus toward businesses’ financial interests and away from worker safety.
“OSHA was designed to be the law, the law of the land, the watchdog, whatever you want to call it. They're supposed to be regulating job sites,” Parsons said. “And part of their job is also to provide contractor assistance and materials to help them comply and just make safe job sites. But the number one thing they're supposed to do is enforce the rules. So if you're treating somebody as a customer, how are you enforcing the rules?”
The Missouri Department of Labor & Industrial Relations confirmed in an email that the state does not have its own workplace heat standard and relies on federal OSHA to enforce workplace safety rules.
According to the AFL-CIO's 2026 “Death on the Job” report, Missouri has 19 OSHA inspectors overseeing nearly 3 million workers. Several outdoor workers interviewed for this story said they had rarely, if ever, seen an OSHA inspector at their jobs.
Heat-related deaths may be undercounted
Without a state-specific heat standard, experts say workers largely depend on the protections their employers provide, which can range from strong safety practices to gaps that leave workers vulnerable to exploitation.
Missouri Department of Health and Senior Services data show 254 people died from heat-related causes between 2014 and 2026. About 6% of those deaths were related to occupational activities.
But researchers say the number of heat-related deaths may be higher because heat is not always identified as the official cause of death.
Jeffrey Shrader, an associate professor at Columbia University's School of International and Public Affairs, said doctors and coroners may be less likely to attribute a death to heat when a person otherwise appears healthy.
“A doctor or coroner is going to be less likely to assume that heat was the reason this otherwise healthy person died,” Shrader said. So that leads folks to focus on, or rather not focus on, workers as a vulnerable group. That's potentially overlooking this group that does actually need some protection from heat.”
A recent NPR investigation found that heat-related deaths are significantly undercounted in federal records. In Missouri, the investigation estimated an average of 192.9 heat-related deaths, compared with 166.9 deaths recorded in federal data — a difference of about 26 deaths.
Missouri also has limited data on workers specifically exposed to extreme heat.
State labor data show that employers and workers filed nearly 1,500 initial workers' compensation reports and claims involving heat-related injuries over the past six years.
Those reports include heatstroke, heat exhaustion, sunstroke and heat cramps.
Could Missouri adopt its own heat protections?
Several states, including California, Maryland, Washington and Minnesota, have adopted workplace heat protections.
Missouri has not adopted a state-specific heat standard.
State Rep. Adrian Plank (D-Columbia) is a union carpenter, and said he would consider proposing additional protections if data show Missouri workers are being harmed and federal regulations are not sufficient.
“Well, I think if you had a real statistical problem, if you had data showing that Missourians are working too hard in extreme conditions and the federal government just isn't satisfying those laws, then yeah, I think Missourians should step in," Plank said. "If we came to know that employers are taking advantage of their employees and working them too hard in crazy conditions, then yeah, I think there should be something that should be done.”
For workers like Morris, staying safe during extreme heat often comes down to the protections their employers provide and their ability to recognize when conditions become dangerous.
Morris said his responsibility to support his 16-year-old son also makes it difficult to simply stop working when conditions become dangerous.
“I'm gonna probably pretty much work till they put me in a casket,” Morris said jokingly.
