The growing market for cool wearables to help beat the heat

Temperatures this summer have been hotter than usual, a trend we have come to expect with climate change as records are continually surpassed. 

While many of us can ride out extreme heat in the comfort of air conditioned interior spaces, outdoor workers don’t have that option and must contend with the risks of serious injury which can be acute and long lasting. 

A fast growing market for wearable cooling products, both in high tech and low tech varieties, is attempting to meet the challenge. Among those products is the CülCan, made by the Tennessee based small business Black Ice.  

“If you can pull heat away from your hand, it'll cool your whole body down. And so that's what we've done with the CülCan. It's basically a five inch cylinder that contains our special coolant,” said Mike Beavers, co-founder of Black Ice. 

A key selling point of the product, according to Beavers, is that the coolant inside, which is a chemical composition Beavers designed, doesn’t get as cold as ice, so it is easier to use on a person’s skin. 

“You put it in ice water or a freezer… and then you just hold it in the palm of your hand,” he said. “That is now our most popular product. We sell tons of those things.”

Beavers said his business has been growing by about 30 percent a year over the last three years, an acceleration from its previous pace. The company has been around for about 20 years. 

Across the Atlantic, the Swiss company GreenTeg is also reporting growing demand for its continuous body temperature monitors, which are worn with a patch or a strap. The monitors are often employed by athletes who have to perform outdoors, said CEO and founder Wulf Glatz. 

“So this device can communicate then with your smartphone,” he said, “and it will estimate your core temperature and broadcast that value to that device.”

Being able to monitor core temperature can help with prevention. Unlike a simple thermometer which, if put against the skin, would only tell you the temperature on your skin, GreenTeg claims its monitors can measure the temperature inside the body. It is that core temperature that is key to whether someone is developing heat-related illness. 

Glatz says there’s growing interest in his company’s technology. They’ve been approached by organizations representing firefighters, the military, miners and airfield workers. 

“If there's an airplane landing, you need to unload the baggage. You can't wait for three hours for it to get cooler, but what you can do is to measure the individuals and really have them safe,” he said, “maybe you need to exchange teams in higher frequency, maybe you need to equip them with cooling gear.”

Brett Perkison, an environmental and occupational medicine specialist at UTHealth Houston, tested one of GreenTeg’s monitors in combination with cooling vests. In a small study, he found the combination approach helpful in limiting heat related illnesses among outdoor laborers. 

The problem with the personal cooling industry is that not all of the gadgets being sold to the public are proven to work. 

For example, ones that use fans to cool the body, such as ventilated helmets, are unlikely to do much in humid environments, said Fabiano Amorim of the University of New Mexico, who has studied heat stress on outdoor workers in Brazil and the U.S. 

“[Helmets with fans] can increase the comfort or let's say your perception to heat, but it's not reducing your temperature,” he said. 

Not reducing core body temperature on hot days can have serious consequences. The number of heat-related emergency room visits in the summer of 2023 totaled 120,000, according to the CDC. 

Heat stress can cause someone to get lightheaded and fatigued. More serious symptoms include seizures. Repeat exposure to heat stress  can permanently damage people’s kidneys, Amorim said. The condition can be fatal. 

“We have seen people 40, 50 years old, [who are] dying from chronic kidney disease. And, they don't have any factor that's related to the traditional chronic kidney disease. That's hypertension, obesity and diabetes. And, the only history these p