Electric Fans Inadvisable In Extreme Heat Unless It’s Humid, Study Finds

Temperature is very high in many parts of the world, including the United States and the Middle East. Several people in these regions use electric fans to get some relief from the heat. But it is not always good to use this device for cooling the body, according to a new study.

The study stated that electric fans can only be effective when it is humid. While the temperature is extremely high and the humidity is very low, a person can feel hotter due to the use of this device, the research stated.

As of now, at least six people died because of heatwave in the U.S. and a red alert was issued in some parts of Europe. People in several middle eastern countries, like Saudi Arabia and Qatar, are also facing problems due to soaring temperatures.

The study published in the Annals of Internal Medicine, which is an internal journal by the American College of Physicians (ACP), on Monday focused on the effects of electric fan use during extremely high temperature.

The research stated that electric fans do not just make a person feel hotter, but this device can also increase the heart’s strain and raise core temperature. The authors of the study also pointed out that current guidelines for this device is poorly based on heat index and not on the actual temperature.

“A combined value such as heat index (HI) is not appropriate for advising whether fans should be used or not,” senior study author Ollie Jay, associate professor in the faculty of health sciences and director of the Thermal Ergonomics Laboratory at the University of Sydney, Australia, told Reuters.

“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,” the researcher added.

During the research, Jay and team found that electric fans can increase cardiovascular strain and also body temperature when the climate is very hot and dry. In other words, “the heart has to do extra work to maintain blood pressure because as one gets hot, blood is diverted to the skin to facilitate cooling and the heart must beat more times per minute”.

“Another form of strain (on the body) is dehydration, which also contributes to increases in body temperature and cardiovascular strain,” Jay added.

For the study, the researchers observed 12 men in different climatic conditions. The participants did not have any medical conditions and they did not take any medications. The researchers observed their body’s ability to thermoregulate through four completed sessions of two-hour each.

They were asked to sit in a climatic chamber that regulated either hot, humid conditions or extremely hot, dry conditions. Though the temperature in the humid condition was lower, the heat index was higher for the humid runs than the arid runs.

The research team measured the dehydration level of the participants by keeping track of their sweat. Meanwhile, their heart strain was assessed and the body temperature of the participants was measured with the help of a three-lead electrocardiography and blood pressure.

While the cardiovascular strain and core temperature reduced with the use of fan in humid condition, it raised in the arid condition, making the participants feel hotter. According to senior author, “the principles are the same for a ceiling fan”.