Scientists from the University of Leeds found that high-powered “jet-air” and
warm air hand dryers can spread bacteria in public restrooms.
germ counts were 27 times higher around jet air dryers in comparison with the
air around paper towel dispensers, researchers found.
“Next time you dry your hands in a public toilet using an electric hand dryer,
you may be spreading bacteria without knowing it. You may also be splattered
with bugs from other people’s hands,” research leader Professor Mark Wilcox
told The Telegraph.
In the study, researchers contaminated their hands with harmless bacteria
Lactobacillus. The contamination was done to mimic the effect of poorly washed
After participants dried their hands, researchers collected air samples around
the hand dryers as well as several feet from the devices. They found the
bacterial counts closer to the air dryers were more than four times higher
than around warm air dryers.
Also, the germs lingered in the air beyond the 15 seconds it takes to dry your
hands — sometimes lasting more than 5 minutes after you leave the
“These findings are important for understanding the ways in which bacteria
spread, with the potential to transmit illness and disease,” Wilcox told The
A spokesman for Dyson — the maker of many jet hand dryers — disputed the
research saying “it’s flawed.”
“They have tested glove-covered hands, which have been contaminated with
unrealistically high levels of bacteria, and not washed,” the spokesman told
A look at the bacteria break down from hand dryers, jet dryers and paper towels. (Courtesy University of Leeds)