Hand dryers spray human waste particles all over you, study finds

You may want to rethink using hand dryers in public bathrooms

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You may think that using a hand dryer in a public bathroom is a far more sustainable and hygienic method of drying your hands than using hand towels.

On the contrary, a recent study has uncovered the disturbing truth that doing so could actually be spreading human waste bacteria far and wide.

Researchers from the University of Connecticut recently conducted a study to determine the extent to which hand dryers spray harmful bacteria when used.

Everyone knows that it’s common decency to close the toilet lid after you’ve been to the bathroom.

However, it’s also a matter of basic human hygiene.

When a toilet is flushed with the lid open, this causes “toilet plume”. When this occurs, microscopic particles of human waste can then be propelled into the air.

That’s not the worst of it, as these particles can then be sucked up into hand dryers before being expelled again with the hot air.

In the study published in Applied and Environmental Microbiology, the team from the University of Connecticut assessed the dryers in men’s and women’s bathrooms in three separate areas.

They used plates to collect the bacteria emitted from the hand dryers and their results will undoubtedly leave an unpleasant feeling in the pit of your stomach.

The plates that were exposed to hand dryer air for 30 seconds collected approximately 18 to 60 colonies of bacteria, while the plates that were simply placed in a bathroom while a fan restributed air for 20 minutes collected an average of 15 to 20 colonies of bacteria.

The researchers concluded that fitting hand dryers with HEPA (high efficiency particulate air) filters could reduce the amount of bacteria distributed by hand dryers.

However, plates still collected bacteria even when dryers were fitted with HEPA filters, which strengthens the argument that hand dryers will always pose a potential health risk.

“These results indicate that many kinds of bacteria, including potential pathogens and spores, can be deposited on hands exposed to bathroom hand dryers and that spores could be dispersed throughout buildings and deposited on hands by hand dryers,” the study stated.