Heat waves are detrimental to the health of outdoor workers, but even indoor workers are at risk as temperatures continue to rise.

A study from nonprofit Public Citizen found that 170,000 injuries and 2,000 deaths from heat stress occur in United States workplaces every year, with nearly half of the deaths occurring on the worker's first day at a job.

In 2019, a study published in the American Journal of Industrial Medicine found that construction workers made up 36 percent of workplace heat-related deaths between 1992 and 2016, despite only accounting for 6 percent of the total workforce.

Those working indoors also face adverse heat, particularly in warehouses or other environments without air conditioning. UPS delivery trucks only recently emerged victorious from a push to equip all vehicles with air conditioning.

Temperatures across the globe are expected to continue increasing with climate change. According to the climate shift index from nonprofit Climate Central, climate change has made the current heat wave in Texas five times more likely. The beginning days of July 2023 were believed to have seen the highest temperatures in over 125,000 years.

Increasing heat from climate change has also exacerbated natural disasters, including the ongoing Canadian wildfires, which have negatively impacted air quality across North America. Fires are more likely to start as conditions become dryer and hotter, leaving outdoor workers to breathe in the smoke while on the job.

Within the next five years, global temperatures are predicted to rise beyond an increase of 1.5 degrees Celsius (2.7 degrees Fahrenheit), according to a report from the World Meteorological Organization (WMO), which said in May that there is now a 66 percent chance of reaching the average by 2027.

“[Heat risk] is certainly getting worse with climate change and as temperature and other factors really have exacerbated the issue,” said Rebecca Reindel, director of occupational safety and health at the AFL-CIO, the largest federation labor unions, via The Hill. She noted that even cleaning up after natural disasters can create “a lot of inequities for folks who need work and are untrained, and are then opened up to dangerous working conditions.”

According to the Public Citizen study, over 50,000 annual heat injuries could be prevented with federal heat protections.