This story is part of Record High, a Grist series examining extreme heat and its impact on how — and where — we live.

Workers at the shipping company UPS have just ratified a union contract that secures wage increases and extreme heat protections for more than 340,000 employees across the country. The deal marks a major win for what organizers have dubbed “hot labor summer,” in which labor fights led by groups ranging from auto workers to Hollywood actors have made headlines in recent months. UPS workers called attention in particular to the dangers posed by soaring temperatures and unsafe working conditions — a key issue in contract negotiations. 

The five-year deal bumps up hourly wages for all employees, ends a two-tier wage system that allowed UPS to pay new drivers less, and eliminates mandatory overtime on drivers’ days off. UPS has also agreed to equip vehicles purchased after January 2024 with air conditioning and to retrofit existing cars with fans, vents, and exhaust heat shields. Leaders at the International Brotherhood of Teamsters, the union representing UPS workers, have called the contract “the most lucrative agreement the Teamsters have ever negotiated at UPS.”

“This contract will improve the lives of hundreds of thousands of workers,” said Sean O’Brien, president of the Teamsters union. “This is the template for how workers should be paid and protected nationwide, and nonunion companies like Amazon better pay attention.”

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The deal was approved by 86.3 percent of unionized workers at UPS. Teamsters said that it received the highest number of votes ever seen for a Teamsters contract at UPS. 

The new agreement highlights how extreme heat has raised the stakes for labor organizing this summer. Relentless heat and humidity in the South, a heat dome stifling the central U.S., and the hottest June and July recorded in world history have created especially dangerous conditions for workers. Heat-related health risks heighten exponentially for people who have to work outdoors or without air conditioning. In the past few months, workers from Greece to Texas have responded by staging walkouts, going on strike, and demanding greater heat protections for workers.  

UPS drivers and warehouse workers say that record-breaking heat waves have rendered the company’s 12-hour workdays and unrealistic productivity benchmarks downright deadly. UPS previously refused to install air conditioning in delivery trucks, claiming that it wouldn’t be feasible due to their frequent stops. “When you open the bulkhead door to go to the back to look for packages, it’s like running into a brick wall — it’s so hot,” said Rick Johnson, a driver who has worked at UPS for 28 years, in a Teamsters video. “You can’t stay back there with the doors closed or you’ll pass out.”

UPS Teamsters and workers hold a rally in downtown Los Angeles on July 19, 2023. AP Photo / Damian Dovarganes

In June 2022, a 24-year old UPS driver named Esteban Chavez died of heat-related heart failure while delivering packages in California. In August 2021, another driver named José Cruz Rodriguez died of heat-related illness on his delivery route in Texas. UPS has reported at least 143 heat-related injuries to the federal Occupational Safety and Health Administration since 2015. 

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Union workers praised the contract for finally including vital protections for drivers working in sweltering conditions. “The A/C in the trucks is something I never thought I would see,” said Keith Short, a UPS worker who participated in the Teamsters strike at UPS in 1997, in a Teamsters video.

A tentative agreement reached between UPS and the Teamsters union last month averted what would have been the largest single-employer strike in U.S. history. UPS workers transport about $3.8 billion worth of goods each day, equal to about 5 percent of the nation’s gross domestic product, according to the U.S. Chamber of Commerce. 

In addition to protecting workers from heat, the contract immediately bumps up all wages by $2.75 per hour, with total wage increases adding up to an additional $7.50 per hour over the next five years. All existing and new part-time employees will receive minimum wages of $21 per hour. The deal also guarantees union members will receive Martin Luther King Jr. Day as a full holiday for the first time, and creates thousands of new jobs during the length of the contract.

UPS called the contract a “win-win-win agreement” when the Teamsters first announced the tentative agreement last month. “This agreement continues to reward UPS’s full- and part-time employees with industry-leading pay and benefits while retaining the flexibility we need to stay competitive, serve our customers and keep our business strong,” the company said in a statement at the time. 

The contract will go into effect as soon as one outstanding supplemental agreement for a local Teamsters chapter in Florida is renegotiated and ratified.