Toilet hand dryers spread more germs than paper towels, according to research published in the Journal of Applied Microbiology.
University of Westminster researchers concluded this by comparing the levels of virus dispersion from using paper towels, a standard hot-air dryer, and a Dyson Airblade jet dryer, after dipping their gloved hands into water containing a harmless virus.
According to their findings, the Dyson dryer's 400mph air blasts are capable of carrying viruses up to three metres across a bathroom. The standard dryer spread viruses 75cm, and the hand towels 25cm.
"The results of this study suggest that in locations where hygiene and cross-infection considerations are paramount, such as healthcare settings and the food industry, the choice of hand-drying method should be considered carefully," the study concluded.
British newspaper The Telegraph reported that a 2014 study by University of Leeds researchers also found that airborne germ counts were 27 times higher around jet dryers in comparison with the air around paper towel dispensers.
The 2014 study was funded by the European Tissue Symposium. A spokesman for Dyson said at the time: "This research was commissioned by the paper towel industry and it's flawed.
"They have tested glove-covered hands, which have been contaminated with unrealistically high levels of bacteria, and not washed."
The Westminster study is the latest salvo in a long-running battle over whether hand dryers or paper towels are more hygienic.
According to The Times newspaper, one test in 2005 - ordered by the German Pulp and Paper Association - found that wiping your hands on paper decreased the number of bacteria on the skin by 24 per cent.
Using a standard hot-air dryer increased it by 117 per cent, possibly because the air stream was contaminated.
Dyson hit back in 2006 with the Airblade, which was endorsed by Britain's Royal Society for Public Health as "a significant step forward in hand-dryer technology and hygiene".
The company argues that its dryers are as good at mopping up bacteria and viruses as paper towels, and better for the environment. It cites four study papers of its own to this effect.
In February, Dyson released an online video hitting back at claims that paper towels are more hygienic than its hand dryers.https://www.youtube.com/watch?v=A10WTBBWy30
Titled "Paper's dirty secret", the video quoted "independent research" as showing that paper towels can contain large communities of bacteria before they even reach the washroom.
It also claimed that up to 88 per cent of unused paper towels contain bacteria.