Hand dryers can be found in many public toilets. Throughout the years, these dryers have changed from being slow and loud into being quiet and super-fast machines that effectively dry your hands in seconds. However, the super-fast hand dryers carry the risk of potential hearing damage.
According to a study, the super-fast hand dryers can have severe effects, as the machines may have the same impact on hearing as a pneumatic drill at close range.
With sound levels of up to 90 decibels (dB), any prolonged exposure to such noise from hand dryers may lead to hearing disabilities as well as hearing loss.
Hand dryers and safety testing
When a new product emerges, it has to undergo certain safety tests for obvious reasons. In this case, the super-fast hand dryers should not have passed the safety tests. But, due to former inaccuracies in past testing conditions, the machines passed the safety tests.
The reason is that the former product tests were performed in product testing labs. These labs were significantly larger than where the hand dryers were to be placed, namely in typical public toilets. The acoustic levels are different in the large labs compared to the levels of small public toilets.
In the recent study, the acoustics of the super-fast hand dryers were instead tested in a lab with a ‘box shape’, which is typical for public toilets to give a more real-life outcome.
The results of the study showed that decibel (dB) levels of the super-fast hand dryers were 11 times as high as the ones reported by the products testing labs.
According to researchers, it is essential to get a more realistic approach in relation to safety tests and to limit usage of super-fast hand dryers in public toilets.
About the study
In the study, a range of product acoustic tests, environmental acoustics tests, noise assessments and interviews with members of the public were involved. The study was carried out by Dr John Levack Drever and his team of sound researchers at Goldsmiths, University of London.