In summer 2021, according to the National Centers for Environmental Information, the United States experienced a dangerously hot summer, breaking records last set during the Dust Bowl. The climate crisis is making heat waves more intense and frequent, endangering workers and communities. Construction workers exposed to hot environments or extreme heat can be at risk of heat-related illnesses and injuries. Heat stress is the combination of a worker’s exposure to heat from physical activity, environmental factors and their clothing, which results in an increase in the body’s heat storage, known as the net heat load.
Chronic heat exposure on construction job sites is a threat to workers’ health and productivity
The correct clothing can protect workers from the effects of heat stress. (Photo courtesy of Ariat)
“Heat stress can cause illness and death,” cautions Sylvia Allen, founder of StaCool Vests, Lecanto, Fla. “Workers on job sites don’t always have the means necessary to avoid heat stress. Drinking water every 15 minutes, shade and rest are not always available. Heat stroke occurs when the body’s temperature-regulating system fails, and the body temperature rises to critical levels. Once the body reaches 104 F, this becomes a medical emergency. Regardless of age or physical condition, it can affect anyone; once a person has had heat stroke or heat exhaustion, they are more susceptible to getting it again. It is also important to consider that hot work environments can also happen indoors.”

StaCool Body Core Cooling Vests can be worn to help prevent the body from overheating. (Photo courtesy of StaCool Vests)
Awareness and Education
Tom Gunsinger, president of Bel-Con Design-Builders Ltd., Belleville, Ontario, Canada, explains that creating awareness and providing proper education are the first steps to protecting workers from heat stress. “Ensure workers understand the dangers and severity of the potential outcomes of heat stress so that all workers do what they can to both look after themselves and to also know what to look for their fellow workers to help keep them safe. We always ensure all sites include heat stress and sun protection safety talks as part of their lunch box safety talks before we get into hot weather.”
At Dallas-based Clune Construction, superintendents and safety managers identify work activities and environmental factors once outdoor activities are anticipated to be performed during high heat temperatures. “We also ensure that plans are in place to protect employees from heat-related illnesses before mobilization,” says Ty Jackson, Clune’s regional safety manager. “We make it a point to emphasize the importance of cool-down stations and proper hydration during our safety meetings. Clune also provides weekly trainings and tool box topics on heat stress prevention. Clune also knows that heat illness prevention starts before anyone sets foot on-site. Employees are trained to identify signs of heat stress and are provided strategies and tips on how to stay cool. We post signage and send out electronic heat stress-related information—in multiple languages if required—to remind employees to monitor and self-assess themselves while working in a hot environment.”

Workers must be protected from the dangers of heat stress on the job site. (Photo courtesy of KPost Roofing & Waterproofing)
At San Diego-based DPR Construction, all workers are trained during first-day onboarding. “Our workers can be successful in preventing heat illnesses by being informed and prepared for the heat while using the tools learned in training,” says Amy Duck, DPR’s safety professional. “Our environment, health and safety (EHS) best practices and plan guides our crews to monitor the heat and weather, so we are prepared ahead of time. We begin talking about heat illness prevention in cooler months before the heat sets in, and we revisit the topic frequently to remind our teams to stay hydrated and fueled. Knowing the signs and symptoms in themselves and others, identifying shaded locations on the job site, and making sure water is available to them are critical factors in reducing heat stress.”
Cooling Gear Cooling gear for construction workers reduces heat stress. Some common gear for construction workers includes cooling vests, sleeves, towels, helmets and bandanas, misting systems, and pop-up canopies. “We have cooling bandanas and towels available to our workers and ensure ample water and a shady rest area is available,” Gunsinger says. “We provide shade and cooling stations, and many workers wear accessories to protect their skin from the heat, like helmet attachments and long sleeves,” Duck says. “We get creative by providing electrolytes and other methods for hydrating our teams on the hotter days. Cooling stations have shade, water and electrolytes.”
Clune Construction recommends its workers wear light-colored, loose-fitting clothing on job sites during high heat temperatures. “There are additional measures we use in some cases where we purchase sun protectors that attach to the brim of your hard hat,” Jackson says. “We can provide cooling wraps for necks or heads and the use of Porta-Cool fans.”

Working during low-sunlight hours can help protect workers from heat-related illnesses. (Photo: Matt Pranzo, courtesy of DPR Construction)
StaCool Body Core Cooling Vests can be worn to help prevent the body from overheating. Allen says this vest is worn under or over clothing and contains cooling packs to help reduce the body core temperature. “The ThermoPaks are frozen and inserted into the vest. They will last several hours then the spare change out ThermoPaks are available for replacement. It is an easy, fast and comfortable application.”
Scott Molina, director of apparel product management at Union City, Calif.-based Ariat, says his company’s technologies like VentTEK, ClimateTEK, Moisture Movement Technology, and lightweight fabrics are found in its Featherlight and DuraLight styles. “[They] are built into our products to help protect wearers from the effects of heat stress.”
OSHA Under OSHA law, employers are responsible for providing workplaces free of known safety hazards. This includes protecting workers from extreme heat. OSHA’s Heat Illness Prevention campaign, launched in 2011, educates employers and workers on the dangers of working in the heat. Through training sessions, outreach events, informational sessions, publications, social media messaging and media appearances, millions of workers and employers have learned how to protect workers from heat. OSHA’s safety message concerning heat stress comes down to three key words: water, rest, shade.
Clune Construction uses OSHA’s heat index app to help it track current weather conditions and change work activities accordingly to mitigate heat related hazards. “We look at their requirements as a baseline and always try to go above and beyond in implementing best practices to protect our employees,” Jackson says.
In terms of regulation, Gunsinger says at Bel-Con, “The Ministry of Labour Inspector will inspect our sites throughout the summer and will ensure we are providing all requirements for our employees in terms of education, proper PPE, water and shelter.”
At DPR Construction, Duck says OSHA sets the standard of care for our workers and has great information to educate DPR teams on preventing heat illness, as well as guidelines for working in the heat. “We follow their guidelines by having a plan and communicating the information to our field teams so they can prevent and recognize symptoms and know how to respond to heat stress. We communicate before the hot season comes, as well as throughout the season. Be prepared, plan for shade, stay hydrated and fueled, and pay attention to your body.”
One way to minimize heat stress is to work on the shaded sides of building during installation. Photo courtesy of Bel-Con Design-Builders Ltd.)