Public toilets may be described as one of the most disgusting place on Earth. According to a study, these toilets tend to be more dangerous if there is a hand dryer on the wall, contrary to the popular belief: dryers are safer than paper towels. The study compared the three commonly employed methods at hand drying: paper towels, jet air dryer and warm air dryer.
According to a research conducted at the University of Leeds, Professor Mark Wilcox of the School of Medicine,demonstrated that the hand dryers, both jet and warm air, spray the germs of the user on to bystanders and in the environment. The research was published in Journal of Hospital Infection
In his experiment Wilcox used a harmless bacteria known as Lactobacillus which is not found in washrooms normally. Applying this bacteria to the participants’ hands, they constructed a scenario which depicted poorly washed hands. When taken to the dryer, the airborne transmission was found to be high due to high levels of lactobacilli in the air. Almost half of the bacteria (50%) persisted in the air even after 5 minutes of drying hands.
The results concluded that the rates of pathogen was highest with jet air spray, which was 4-5 fold higher than that of warm air dryer and 27 times higher than the ordinary paper towel. The transmission through paper towels was the lowest.
Looking into the matter of droplet dispersal, the team coated the hands of the participants’ hands with paint and found that the rate of water droplet dispersal was, again, highest with jet air dryer. With it being lowest with paper towels.
“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,” said Professor Wilcox.
The team deemed air dryers a risk to public health in areas of high exposure to a variety of organisms such as hospitals.
“These findings are important for understanding the ways in which bacteria spread, with the potential to transmit illness and disease,” he concluded.