Health warning issued over hand dryers

"Super fast" hand dryers may reduce people's time spent in a public toilet but for some the devices are causing "unwelcome stress", researchers said.

The "ultra rapid" cold air hand dryers can have the same impact on the human ear as a road drill at close range, a study suggests.

Researchers from Goldsmiths, University of London, said that the high speed dryers can cause discomfort to elderly dementia sufferers, affect the navigation of visually-impaired people and even force hearing aid users to turn their devices off when entering public toilets.

An acoustic test in a typical "box shape of a public toilet" found that the sound decibels reached by the dryers could reach 11 times more than those recorded in product testing labs.

And interviews with members of the public found that the devices can have a "negative" impact on some people with hearing or sight problems and dementia sufferers.

Lead author Dr John Levack Drever, head of the unit for sound practice research at Goldsmiths, said: "Manufacturers tend to test hand dryers in ultra-absorbent acoustic laboratories which is perhaps why actual sound levels are so much higher than those advertised.

"From this initial study it is evident that 'ultra rapid' cold air hand dryers are loud, and this loudness is vastly amplified in the highly reverberant and reflective small toilet.

"A wide range of vulnerable subgroups are being seriously affected by hand dryer noise, resulting in unwelcome stress in this sensitive space, and in extreme cases people are being excluded from public spaces, the workplace and schools.

"To solve these issues, we propose that engineers, sound artists and users come together to look at the acoustic space in which these dryers are found and tune the products accordingly to enhance the listening experience and minimise the discomfort that is caused to a whole range of people."

Dan Pescod, campaigns manager at RNIB, a charity for blind and partially sighted people, added: "Anything which masks ambient sounds could be a problem for a person with sight loss, to a greater or lesser degree. As hand dryers are often situated by doors, loud models could increase the likelihood of a person with sight loss having an accident. RNIB suggests that manufacturers should consider this risk when designing hand-dryers."