Too Hot to Work

The report finds that without action to reduce emissions, outdoor workers in the US will face a three- to fourfold increase in exposure to dangerous heat (heat index above 100°F) by midcentury, putting up to $55.4 billion in annual earnings at risk. It highlights that Black/African American and Hispanic/Latino workers are disproportionately represented in outdoor occupations and will bear a heavier burden of these losses. The authors argue that current voluntary heat guidelines are insufficient and call for the enactment of the Asunción Valdivia Heat Illness and Prevention Act of 2021 to establish mandatory, enforceable federal heat safety standards.

• Approximately 32 million workers in the United States are employed in occupational categories where two-thirds or more of the jobs require outdoor work, including construction, farming, and protective services.
• Outdoor workers face significantly higher mortality risks from heat than the general public, and Black/African American and Hispanic/Latino populations are disproportionately represented in this workforce, comprising over 40 percent of outdoor workers compared to 32 percent of the general population.
• By midcentury, if no action is taken to reduce global emissions, the exposure of outdoor workers to days with a heat index above 100°F—the threshold where the CDC recommends reducing work hours—is projected to increase three- to fourfold, rising from a historical 315 million person-days per year to 1.4 billion person-days per year.
• Extreme heat is projected to put between $39.3 billion (slow-action scenario) and $55.4 billion (no-action scenario) of outdoor workers' annual earnings at risk by midcentury. In the no-action scenario, over 7.1 million workers would see 10 percent or more of their annual earnings at risk.
• The economic impact of extreme heat will disproportionately affect workers of color, with Hispanic/Latino workers facing an estimated $11.2 to $16.1 billion and Black/African American workers facing $5.2 to $7.5 billion in annual earnings at risk.
• Current heat protections in the US are largely voluntary recommendations from OSHA and the CDC; only California and Washington State have established enforceable heat-related protective standards for outdoor workers.
• The report advocates for the passage of the Asunción Valdivia Heat Illness and Prevention Act of 2021 to mandate a federal heat health protective standard enforceable by OSHA, including requirements for hydration, shade, and rest breaks.

APA

Union of Concerned Scientists (2021). Too Hot to Work. https://www.ucs.org/sites/default/files/2021-09/Too-Hot-to-Work_9-7.pdf

Chicago

Union of Concerned Scientists. Too Hot to Work. 2021. https://www.ucs.org/sites/default/files/2021-09/Too-Hot-to-Work_9-7.pdf.

Wikipedia

{{cite report |author=Union of Concerned Scientists |title=Too Hot to Work |date=August 2021 |url=https://www.ucs.org/sites/default/files/2021-09/Too-Hot-to-Work_9-7.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{unionofconcernedscientists2021too, author = {{Union of Concerned Scientists}}, title = {{Too Hot to Work}}, institution = {Union of Concerned Scientists}, year = {2021}, month = aug, url = {https://www.ucs.org/sites/default/files/2021-09/Too-Hot-to-Work_9-7.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }