However, they have achieved this great performance improvement by working out ways to spin motors faster and therefore move large amounts of air more quickly. Both of these things cause more noise, and it is now the case that hand dryer noise has become at least a talking point, if not a cause of annoyance for many people.
In fact, we find ourselves dealing with more and more customers who are replacing their hand dryers because of noise problems - whether it is because in an office environment the noise of hand dryers in a washroom can be clearly heard in the next door conference room, or because children run out of the washroom scared of the noise!
The response from the hand dryer manufacturers
The response from the manufacturers, eager both to make sure that their product is not labelled as an unbearably loud hand dryer which makes children cry and deafens old ladies, is that the majority of them now claim to be either very quiet (using the ‘Quiet Mark’ accreditation) or have new ‘reduced noise’ models, and they have indeed invested a lot of R&D cash to make sure they can accurately claim these things.
However, we shouldn’t let the issue of noise get out of hand – despite claims from various quarters, there is not a hand dryer on the market which is ever going to cause any hearing damage (see the comparative chart above - most hand dryers are in the range of 72 – 82 decibels). And we should not forget that by and large, (although there are some notable exceptions) the noise of a hand dryer is directly related to its power and effectiveness, so going for the quietest dryer will usually mean we are not buying the most powerful dryer.
Accurate hand dryer noise measurement
Unfortunately, outside the ‘hand dryer labs’ of the manufacturers, in the real world there are quite a few barriers to being able to properly evaluate whether a hand dryer will be too loud for your situation. These include:
- Decibel ratings are not simple to compare. They are on a logarithmic scale, so 81 decibels is actually close to 50% of 85 decibels.
- It is one thing to measure the noise output of a dryer in the lab, but in real life, putting your hands in the airstream can make a huge difference. For example, with a hands-under dryer, the airflow is completely unobstructed after leaving the dryer outlet, but in real life, it immediately comes into contact with the users hands and so generates a lot more noise.
- Similarly, the acoustics of the washroom will affect things in a very unpredictable way – a washroom is usually a pretty small room, and doesn’t typically have much in the way of sound-absorbing furnishings – both of these are things which will make a big difference to the apparent volume of the dryer.
So what can we make of all this?
So in reality, we recommend using the published decibel ratings for hand dryers as a rough comparative guide only, and do bear in mind that, all other things being equal, there is typically a tradeoff between noise and power, so the quietest hand dryer is unlikely to be the most powerful.
What we would advise against, is making the mistake we have seen several times, which is that, faced with a very loud hand dryer, the response has been to replace it with the quietest possible alternative. In all cases where this has happened, the customer has disappointed in the performance of their new dryers - even if they are delighted by how little noise they make!
If you are in any doubt at all as to whether the dryer you have chosen may be too loud, do get in touch on 01934 253600 to talk it through and help you confirm the priority of your requirements.
