As much of California endures triple-digit heat this week, indoor workers are receiving immediate protection from extreme temperatures.

While California has had heat regulations for outdoor workers since 2005, the state announced on Wednesday that it has finalized new rules for indoor workers after a swift review process. The Occupational Safety and Health Standards Board approved the regulation last month, and it has now passed the necessary legal review.

“This regulation offers critical protections for workers throughout California and assists employers in addressing the challenges posed by rising indoor temperatures,” said Debra Lee, chief of California’s Division of Occupational Safety and Health.

California is among a few states that are implementing worker safety standards in response to the escalating effects of climate change and extreme heat. Earlier this month, the Biden administration also proposed federal regulations aimed at safeguarding both indoor and outdoor workers from heat exposure, as extreme heat becomes increasingly hazardous.

Under California’s new standards, indoor workplaces must maintain temperatures below 87 degrees Fahrenheit when employees are present, and below 82 degrees in areas where workers are wearing protective clothing or are exposed to radiant heat, such as near furnaces. For workplaces without air conditioning, alternatives like fans and misters can be used to lower the temperature.

The new regulations offer flexibility for businesses unable to sufficiently cool their workplaces. In such cases, employers must provide workers with access to water, regular breaks, designated cooling areas, cooling vests, or other methods to prevent overheating.

However, businesses, particularly small ones that do not own their properties or are located in older buildings, are concerned about the costs of compliance, according to Robert Moutrie, a senior policy advocate at the California Chamber of Commerce.

“The most straightforward solution to this regulation is air conditioning, but it’s a significant expense,” Moutrie said. “For small businesses that lease their spaces, making changes like adding cooling areas is not always feasible.”

Development of the regulations began in 2016 but was delayed, partly due to the COVID-19 pandemic. The worker safety board requested an expedited process to prevent a delay until fall, which would have left workers vulnerable to summer heat.

The regulations cover most indoor workplaces, including classrooms and delivery vehicles, but exclude prisons and local correctional facilities. The Governor’s Office projected that implementing the regulations in these facilities could cost the California Department of Corrections and Rehabilitation billions of dollars.

The board plans to draft a separate set of regulations for workers in the state’s 33 prisons, conservation camps, and local jails, which could take up to a year or more to complete.

The Department of Health and Human Services reported 1,602 heat-related deaths in 2021, though this is likely an undercount as reporting is not mandatory. The number increased to 2,302 in 2023, though it is unclear how many of these were work-related.

Meanwhile, global temperatures set a record high in June for the 13th consecutive month.

“This represents one of the major safety issues faced by workers across California in various industries,” said Tim Shadix, legal director at the Warehouse Worker Resource Center, which advocated for these protections. “And the situation is worsening with climate change and increasingly hotter summers.”