Study suggests that SOME hand dryers may cause damage - A reality check, don't panic!The alternate view

Written by our colleague Andrew Cameron in the UK.

It is interesting that the press coverage has generalised that hand dryers per se cause hearing damage for children, when the study actually shows that SOME hand dryers may be too loud if there was exposure over prolonged periods of time.

SOME not ALL and largely only if exposure was far longer than it would ever be. The timing of the reports release to the media just before the school summer holidays despite being conducted between 2015-17 seems more than coincidental.  Schools tend to replace their paper towels with hand dryers in the school holiday due to the massive cost, cleanliness and environmental savings at this time of year.

This reeks of the paper towel industry’s PR juggernaut continuing to find every angle to do down hand dryers and continue their mass profit from deforestation.

The loudest recorded measurement was 117 dB(A) for the Xlerator which is a product we consciously don’t offer due to the noise output. No one in their right mind would ever put this in a location frequented by 3-year olds, although we have seen it in airports and support the study in highlighting why this is not good. 

As a manufacturer/supplier of hand dryers we have championed for years the need to have an appropriate dryer sited at anappropriate height for both children and disabled users. We specifically make the same points that the study highlights, that dryers need to be lowered for use by young children (this would radically change the results of the report as hand dryers for children would be installed a height well below ear level) and also that a quieter option should be selected.

As such we make very particular recommendations for nurseries, primary schools and public attractions/locations frequented by children.  It is important always to have a children’s dryer available at a lower height with some distance from the other dryers in any multi-age use washroom.

We also have the most hand dryers on the market that are assessed and verified by Quiet Mark to be some of the quietest in their class.

Quiet Mark is the International award programme for low-noise, high performance technology and solutions to combat global noise pollution. The Quiet Mark is associated with the Noise Abatement Society whose work helps to relieve the physical and mental distress and ill health which noise and related pollutants cause and which profoundly affect public health.

To give a little more perspective into the recommended maximum exposure to noise for adults is shown below. 140 dB(A) is stated by the World Health Organisation as instant hearing damage, 120 dB(A) for children. If you apply similar ratios to below for children it is true that if Children were exposed to most of the hand dryers in the test for in excess of an hour a day, there maybe an issue, however a small child will be likely to use a noisy hand dryer for less than 10 seconds and a quieter dryer for less than 20 seconds.

NIOSH Daily Permissible Noise Level Exposure

Hours per day / Sound level:

  • 8 hours = 85dBA
  • 6 hours = 86dBA
  • 4 hours = 88dBA
  • 3 hours = 89dBA
  • 2 hours = 90dBA
  • 1.5 hours = 92dBA
  • 1 hours = 94dBA
  • 0.5 hours = 97dBA
  • 0.25 hours or less = 100dBA

We do also call into question some of the data collected. All the db levels are surprisingly high and in no way similar to the hundreds of tests we have done on the likes of the Mitsubishi Electric Jet towel, which simply is not as loud as recorded in this study. We would happily provide a live test to show this. We have located many Mitsubishi Electric units in noise sensitive areas with 100% satisfaction. It is also worth noting that the test seems to look at the old Dyson V model not the acoustically improved HU02 version.

We don’t want to be chastising the 13-year-old girl who conducted this research.  Establishing the truths and facts through science should certainly be commended.  However, we need to look at it in more depth because of how the media are scaring the general public again with their headlines and mis representation of the actual study they are referring to.

I’m sure when she conducted this study, she didn’t realise the paper towel PR machines would be using it for their own profitable gains.  Her main purpose was to test a hypothesis she had and produced the science.  In that respect we encourage her to keep going and carry on her work. To get a piece published in a Journal is an outstanding achievement, providing a role model for other budding scientists.

However, there are some issues that need highlighting.  As an example, the young scientist has referenced there is a suggestion that children perceive noise at up to 20 db louder than adults and concludes that there is no safe duration of exposure for children to sounds greater than a level between 91 to 111 db.  However, the reference she states this information from is not from the scientific literature.  It is a comment made in a general blog post from Audiophile Audition (no longer accessible) which “is a free international online magazine for audio buffs, record collectors and music lovers”.  There was no reference to accompany this statement to check its accuracy. Therefore, no creditable science to back up this kind of conclusion.

There is also a suggestion in the study presented that NIOSH have determined that there is no safe duration of unprotected exposure to sounds greater than 111 dB. Although on reviewing the literature they reference, it looks like you are still ok to have 11 seconds of exposure at 119 dB.

Again, we are not highlighting this to criticise her personally, it is great that she has used references to back up her study. But, the way in which this work has been used to tarnish the name of all hand dryers means we need to highlight its flaws.

In summary, this is a good study to highlight an issue that the hand dryer industry is already aware of and has made excellent strides in producing quieter, effective products. It is also really important that facilities are not influenced negatively by generalised headlines when hand dryers are doing so much good to cut global waste.

Our small business alone has recommended and supplied over 40,000 appropriate hand dryers that prevent 112,000 Virgin trees needing to be felled per year. Paper towels are not recyclable as they are contaminated waste and the stock of recycled paper is not enough for a circular economy, so deforestation is continuing at an alarming rate. The lungs of the earth are being restricted and non-renewable resources are being used to do it, a cycle of destruction in the pursuit of profit from single use products.

Get the correct hand dryer, put it at the right height and there is 100% no risk of any hearing damage. I personally know deforestation, unnecessary manufacturing, transport and energy use is the real threat hear to our children’s future!