When temps are dangerously high and humidity is low, fans can actually make a person feel hotter, increasing strain on the heart and raising core temperature!
In extreme heat, electric fans may offer some relief when it's very humid, but when temps are dangerously high and humidity is low, fans can actually make a person feel hotter, increasing strain on the heart and raising core temperature, a new report warns.
The authors point out that current guidelines for fan use are based on the "heat index" rather than the actual temperature, but "a combined value such as heat index (HI) is not appropriate for advising whether fans should be used or not," said the study's senior author, Ollie Jay, associate professor in the faculty of health sciences and director of the Thermal Ergonomics Laboratory at the University of Sydney, Australia.
The authors point out that current guidelines for fan use are based on the "heat index" rather than the actual temperature, but "a combined value such as heat index (HI) is not appropriate for advising whether fans should be used or not," said the study's senior author, Ollie Jay, associate professor in the faculty of health sciences and director of the Thermal Ergonomics Laboratory at the University of Sydney, Australia.
Jay added, "In very-hot dry conditions the HI was relatively lower, yet fans were detrimental; but in hot-humid conditions the HI was relatively higher and fans were beneficial."