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Illustration by Security Management; iStock

Extreme Heat Waves and Deaths Drive Concerns About Workplace Safety

It has been a scorcher of a summer so far in parts of the northern hemisphere. This year featured the hottest June ever on record for the United Kingdom, with an average mean temperature of 15.8 degrees Celsius (60 degrees Fahrenheit) and multiple days reaching the low-30s Celsius (high 80s Fahrenheit).

But while those temperatures drove many to parks and beaches to enjoy warm weather activities, other heat waves have been much more intense—and deadly.

An early heat wave rolling over Spain in June left residents—especially those with disabilities—at high risk of death, as well as physical, social, and mental health distress.

In India, hundreds of people came down with heat-related illnesses during a heat wave that reached upwards of 116 degrees Fahrenheit (47 Celsius) and lasted for more than 17 days in some parts of the country. “The combination of prolonged heat, high day temperartures, and high humidity made it a heat stress disaster,” The Hindustan Times reported. The conditions had the potential to kill thousands of vulnerable people, and the death toll from this wave of extreme heat is still unknown.

A three-week heat wave in June strained the Mexican energy grid. Temperatures climbed close to 122 Fahrenheit (50 Celsius), and at least 100 people died due to heat-related causes, Reuters reported.

Cities in the American West—including Phoenix, Arizona, and Las Vegas, Nevada—have been bracing for extreme temperatures. The heat index in Las Vegas is expected to hit 104 degrees Fahrenheit (40 Celsius) today; in Phoenix, highs are predicted to remain above 100 degrees Fahrenheit (38-43 Celsius) for the following week. Heat indexes are calculated by combining the air temperature and relative humidity to determine what the temperature feels like to the human body—increased humidity makes it more difficult for people to regulate their body temperatures, as perspiration cannot evaporate.

More than a dozen people died across the United States due to heat-related complications in the past few days, the BBC reported. A U.S. Postal Service worker collapsed in a customer’s yard in Texas and was pronounced dead at the scene after working in extreme heat—the heat index topped 110 degrees Fahrenheit (43 Celsius) that day. An Amazon delivery contractor was filmed swooning in the Texas heat last week.

While hundreds of people in the United States die from heat-related causes every year, the U.S. Department of Labor (DOL) announced a “national emphasis” program last year to focus on the issue as it relates to workplaces, warning that “heat illness—exacerbated by our climate’s rising temperatures—presents a growing hazard for millions of workers.”

The DOL reported that 36 work-related deaths in 2021 were due to heat exposure, but workplace safety advocates say those figures are low. Progressive non-profit Public Citizen told the BBC that heat exposure is responsible for as many as 2,000 worker fatalities and up to 170,000 workplace injuries every year in the United States.

There are four main classifications for extreme heat, according to the U.S. National Weather Service.

  • Caution
    • Heat index: 80-90 degrees Fahrenheit
    • Effect on the body: Fatigue possible with prolonged exposure and/or physical activity
  • Extreme Caution
    • Heat index: 90-103 degrees Fahrenheit
    • Effect on the body: Heat stroke, heat cramps, or heat exhaustion possible with prolonged exposure and/or physical activity
  • Danger
    • Heat index: 103-124 degrees Fahrenheit
    • Effect on the body: Heat cramps or heat exhaustion likely, and heat stroke possible with prolonged exposure and/or physical activity
  • Extreme Danger
    • Heat index: 125 degrees Fahrenheit or higher
    • Effect on the body: Heat stroke highly likely

The National Weather Service currently warns that a heat wave across the Southern United States continues to be oppressive, with heat indices approaching 105-110 degrees today in some places. Temperatures in some areas of California and the Desert Southwest are likely to reach well into the triple digits today.

The U.S. Occupational Safety and Health Administration (OSHA) provides a number of resources for employers and workers about safety in high temperatures. It noted that “Employers are responsible for providing workplaces free of known safety and health hazards. This includes protecting workers from heat-related hazards.”

By law, OSHA said, employers must provide workers with water, rest, and shade; allow new or returning workers to gradually increase workloads and to take more frequent breaks during the first week of work as they build a tolerance for working in the heat; plan for emergencies and train workers on prevention; and monitor workers for signs of illness.

Early warning signs of heat illness include headache or nausea; weakness or dizziness; heavy sweating or hot, dry skin; elevated body temperature, thirst, or decreased urine output. In these cases, employees should be given water, moved to a cooler area, and monitored. Signs of a medical emergency include abnormal thinking or behavior, slurred speech, seizures, or loss of consciousness; in these cases, emergency services should be called immediately and the worker needs to be cooled down right away with water or ice, OSHA advised.

Workplaces can include more heat-related hazards than other locations due to workers’ physical activity—which drives up body temperatures—and other sources of heat, such as machinery and furnaces. OSHA recommends using a wet bulb globe temperature monitor to measure workplace environmental heat more accurately so employers can make safety decisions with more data. OSHA also recommended tasking and training an individual on-site at worksites to monitor conditions and implementing the employer’s heat plan throughout the workday.

While there is not a national heat exposure standard for workplaces to follow, some U.S. states have specific guidelines. For example, California’s Heat Illness Prevention Standard requires employers to provide training, water, shade, and planning around heat-related worker risks at outdoor worksites. The DOL started crafting a national rule for employers in 2021, although this process is likely to take years.