My kids get nervous as soon as they even see a hand dryer. They start crying when it's on. I thought they were exaggerating, it never occurred to me that sound levels for kids are different because they are smaller (though it makes complete sense). That, coupled with higher sensitivity to noise and more delicate hearing canals of youngsters kind of make me feel like a bad parent for trying to let them use the dryers anyway (Even though I have long since given up). This kids research proves my kids right, and I am not easily convinced ;) Great accomplishment for I should listen to my kids.
Already an impressive combination of curiosity and perseverance to get a scientific paper published for any non-academic, let alone a 13 year old!!
Wow, I was recently in an airport bathroom where a young boy absolutely refused to wash his hands. His father was extremely patient and said that he needed to wash his hands. The boy was near tears saying that they would miss their plane. It was all a really strange and illogical situation. Until I read your sentence. I don't know if this is why the boy wouldn't wash his hands, but it makes me realize that sometimes kids have reasons for what they say or do, even if they can't explain it. Reminds me of the hand licking incident: https://news.ycombinator.com/item?id=18842009
I thought I had read all about the hand licking incident and learned not to make presumptions about kids. Today, I realize that the lesson hasn't really been ingrained into me yet.
That's not the only reason why children hear more and louder. When you're in your '30s you already have a minor hearing loss, you don't hear all sounds and noises then you did when you were 5. Children see more colours as well.
You know what really hurts my years? As a child, and even now? Airplane toilet flushes. I always wish there were a 20 second delay so I could hit it, wash my hands and run out of the bathroom.
Kids can also be over-sensitive to certain kinds of sounds. This is related to sensory integration and in some people the neural system adjusts automatically, while others might require SI therapy. This over-sensitivity is not due to the volume itself, but occurs later in the neural processing.
I've seen it myself: a child would have no problems with loud music, but any kind of noise (as in, white noise) would be painful. This included hair dryers, vacuum cleaners, some power tools, and sounds of water/sea.
Shoot, I get nervous and feel like crying when I see a hand dryer, and I’m in my mid 30s.
Those devices are literally painful for me to be around. I view them as a scourge and will consider not washing my hands if there’s no soundproofed alternative.
I know the professional dryer my mother uses is specifically designed to put out good airflow but does so with by using a slower speed but larger vane fan. the motor and input is near the user with a long exhaust tube exiting near where the dog is, they are always mounted to allow ease of movement.
My personal least favorites are the Excel dryers, which seem to be becoming quite common. They may be reasonably loud when your hands aren't beneath them, but they become unreasonably loud when you put your hands in the air stream and start rubbing them together. I find that you get white-ish noise/half-whistling noises at an absolutely miserable level.
Many years ago, I actually had a desk in an office that was maybe 10-15 meters from a nearby Excel hand dryer, separated by two doors. I hated it with a passion. Every time somebody dried their hands, I'd hear it. I left that job for a lot of reasons, and the hand dryer wasn't exactly one of them, but I wasn't sad to be rid of it.
And I'm not 9. I'm 35. I find that I have pretty good hearing, at least as compared to my partner.
What gets a little weird is that since leaving software and making a career change to woodworking, I've gotten more sensitive to loud noise. I used to take the subway to work like many other people. Now, I find that the noise of the train is too loud.
I'm religious about wearing hearing protection in the shop. I don't know if my hearing has gotten objectively better, or if I'm just more aware of loud noise than I used to be. It'd be hard to do a study on that without a time machine though.
I’m interested to hear about your switch from software to woodworking. How did you get started? Do you make money by building pieces on commission? Are you glad you made the switch?
Misread it as "hair dryer" at first, but the principle is similar...
Fans are loud, especially small powerful ones. There's plenty of other comments here complaining about the Dysons, and I agree; and I also much prefer the older ones (with a heater), which seem to have a far slower fan and a deeper note. That said, I find towels/paper most effective for drying.
But if insisting on air drying, perhaps a design with the blower elsewhere (maybe centralised, like a vacuum --- another fanned device that's also very loud), a local heater, and slower air flow would be more ideal.
My daughter is 4 months old and absolutely loves the sound of both our (very cheap) hair dryer and our (even cheaper) vacuum cleaner. I think it is essentially white noise to her, as she also loves the sound of running water. We know a couple where the father actually made a 30 minute mp3 of their hairdryer blowing to get their daughter to sleep.
That being said, even I cannot stand the sound of hand dryers in public restrooms. To me, it basically sounds like an extremely hysteric hair dryer. I wonder if it has anything to do with the fact that they are mounted on a wall, which gives them more resonance.
A few days ago I stood before the hand dryer in my office bathroom (or at least I think it was a hand dryer, as it was mounted waist high to the left of a sink) and puzzled at its labeling. I even took a picture:
There's no shower anywhere nearby, but this object which I consider to be obviously a hand dryer is labeled "hair dryer". Surely the people who make these know what they're for...
And I agree, a large tank of compressed air with an on-demand heater on the human end would be pretty nice.
Interestingly, the Dyson hair dryer my wife has is quieter than our dyson vacuum, which works out great since I'm often on the phone for a daily meeting while she's drying her hair. She says it's a little faster at drying her hair than the average hair dryer too, but it blows air differently so it requires a little different technique to use.
Most of us outgrow and then forget how cool water makes small children shiver, hunger and sun makes them weak, bitter vegetables are overpowering, sitting on grass without pants is painful, so is affection, unpolished wooden benches, men's stubble etc.
It's odd that this article popped up, as I have been recently thinking about noise pollution when walking my dog around the outside of my neighborhood. My unscientific guess is that 50% of vehicles that pass by are significantly louder than they ought to be, and my further guess is that at least half of those vehicles are louder because the driver desires it. In the grand scheme of the world's problems it is probably very low on the list - but I'm guessing it negatively affects people, animals and insects more than you would expect. Would it be so difficult for noise pollution to be regulated like emissions (in fact, couldn't it be done in the emissions process most states in the USA perform?)
I wonder if anyone has considered reverberation in these measurements. It's going to make the noise louder than it would otherwise be.
Basically, the loudness of a sound hitting your ear is a combination of multiple factors:
1. How loud the sound source is.
2. How close your ear is to it.
3. How much it reverberates or dissipates.
Imagine if a hand dryer were installed outdoors in an open field. Sound would emanate from the dryer, then wander off never to return.
Now imagine a hand dryer in a room with carpet and some soft furniture like a couch. Sound would emanate from the dryer, and some of it would hit surfaces that absorb it. But some of the sound would also hit reflective surfaces like walls or glass, and that reflected sound could come back to your ear and increase the total noise level.
Now consider what a bathroom is like. For ease of cleaning, it's entirely hard surfaces. Concrete, porcelain, tile, metal, etc. These absorb almost no sound. And bathrooms are typically pretty small rooms. It's basically the worst case for taking an already-loud thing and making nearly all the noise reach your ear.
Hand dryers can also spread airborne bacteria onto your hands. Perhaps modern dryers include intake filters to address this issue, but the filter would need replaced on a regular schedule, which is probably not a realistic expectation for most restroom facilities.
For what it's worth, the two models singled out in the article are the MOST common at restaurants near me new enough to have recently reno'd their bathrooms. I don't know if they're cheap, or if they're "fancy" so they're trendy, or if it's some weird American thing about having the SUV of hand dryers, but the Xcelerator and Dyson things are _endemic_. My 6yo has been complaining about them for years and not once did I ever tell him he was wrong; in fact I've taken to just walking back to my table with wet hands and drying them off with a napkin if they're going to be serving me the shit sandwich of hearing damage for washing my hands.
I think the simplest solution would be for municipalities' health departments to outlaw them, or at least set VERY conservative noise limits.
I hate air dryers perhaps slightly too vehemently. I think it would be a net positive even if they were simply removed from everywhere without replacement.
I'm not sure why they're so common given that they seem to only make things worse.
> I'm not sure why they're so common given that they seem to only make things worse.
Air hand dryer:
One purchase - zero daily maintenance needs.
Paper towels:
Continuous purchase expense (buying new stock) - continuous daily maintenance needs (resupply of dispenser), increased refuse expense (all the discarded paper towels increase the refuse stream size).
When you tally up the expenses for "air dryer" vs. "paper towels" for a busy restroom and over a reasonable time span (say 1 year) the cost differential is why air dryers are so common.
Of course, some owners also advertise the environmental aspects, but the true reality is the air dryer is there because it saves the restroom owner a significant amount of money each year.
> I hate air dryers perhaps slightly too vehemently.
When I was little I used to be worried they would eat my fingers, particularly ones that looked like https://i.imgur.com/hCMAQV7.jpg with that little shiny metal dome. It kind of made me think it was hot and i'd somehow burn myself.
I wonder whether those super-fast ones (like the dyson airblades) are better or worse for children these days.
I've always used my clothes over an air hand dryer. You know they have to be nasty because of all the water blown off hands that are likely only marginally cleaner than before washing, and that nastiness gets aerosolized and spread around the entire bathroom. The front and sides of my pants to wick enough water away so I can use my hands while they air dry the rest of the way: problem solved.
I don't usually wish cartoonish misfortune on anybody, but I make an exception for the person who decided that the infant changing table should be installed right next to the Dyson air dryer in a certain popular retail store.
That person should have a piano dropped on them.
It's awesome that this young scientist decided to investigate and call attention to this issue, and even better that she's resolved to help come up with solutions!
I don’t mind them in general. Some of the new high speed ones are absolutely horrendous in this regard. Literally hurts my ears even a couple meters away
My daughter refuses to use the big, tank less toilets that you find in public restrooms because she's scared of them. Never thought the noise level could be an issue in the origin of her fear but these things are loud when they go off and most are now motion activated so they trigger as soon as you get up.
This all makes more sense now, thanks to this kid for this, I've never realized how noise was different for kids.
It's clear to me that whatever costs savings there are in using these electric dryers is not worth it considering A) they aren't even sanitary which defeats their entire purpose and B) they are dangerous to childrens ears.
We really should just mandate that public restrooms use Cloth Roll Towel Systems for hand drying. It's economical in the long run, not a giant waste of resources, and it is proven to be more sanitary than paper hand towels!
My daughter is deaf in one ear, so cannot localize sound nor can she sense distance. There are two things that absolutely terrorize her: fireworks and air dryers.
The Dyson airblade is the fucking worst. In addition to apparently being one of the louder ones, it's also one of the most unhygienic. It blows the germs off of your hands and onto your face. You should avoid them like the actual plague.
Dyson equipment (I have an Animal vacuum cleaner too (it was a gift)) falls into the category of "surely this breaks some kind of regulation". The sound levels are way above my pain threshold. My only explanation is (seriously) that everyone invovled in designing, building, testing and marketing must have hearing problems.
And yet, they're seen as a medium-high-prestige item.
I’ve always thought it was disgusting that I’m raising / lowering my hands into a narrow slot where I’m bound to touch the sides - sides where others (who might’ve washed their hands less well) have also been depositing a germ factory.
Depends which model, the V which I've used in many gas stations is one of the best in my opinion, blows air through a narrow opening and you don't have to touch it.
Edit: if you find the older ones disgusting, make sure to let the place of business know by complaining to them, otherwise they're never going to change them unless they break.
When it comes to the standard air blade, I don't think your concerns about hygiene are valid. You have, after all, just washed your hands. Any "germs" have already been killed and washed away by soap and water. If anything is blowing on to your face (not the case in my experience), it's just water vapour from your own hands.
There is, however, another Dyson design where the hand dryer is integrated into the sink/tap. This one actually blows particles/droplets from the sink up towards your face, which does give me some hygiene concerns:
Sadly it's because manufacturers deliberately make them loud to make it seem like they're doing their job more. It's the same with many garden tools. Lawnmowers, leaf blowers and hedge trimmers can be made very quiet but they're deliberately made loud to make it feel like they're doing their job more.
Yes! This is so awesome to see! And it has nothing to do with the researcher being 13. We are constantly bombarded with loud noises (don't get me started on motorcycles and construction noise) that do long-term damage to our ears. I hope that one day we can regulate these noises in public spaces. Today it starts with study.
[+] [-] tda|6 years ago|reply
Already an impressive combination of curiosity and perseverance to get a scientific paper published for any non-academic, let alone a 13 year old!!
edit: The absolute worst things are these https://www.ehanddryers.com/hand-dryers/tap-hand-dryers, my kids just plain refuse to wash their hands out of fear of accidentally triggering the dryer
[+] [-] PakG1|6 years ago|reply
Wow, I was recently in an airport bathroom where a young boy absolutely refused to wash his hands. His father was extremely patient and said that he needed to wash his hands. The boy was near tears saying that they would miss their plane. It was all a really strange and illogical situation. Until I read your sentence. I don't know if this is why the boy wouldn't wash his hands, but it makes me realize that sometimes kids have reasons for what they say or do, even if they can't explain it. Reminds me of the hand licking incident: https://news.ycombinator.com/item?id=18842009
I thought I had read all about the hand licking incident and learned not to make presumptions about kids. Today, I realize that the lesson hasn't really been ingrained into me yet.
[+] [-] akerro|6 years ago|reply
[+] [-] dheera|6 years ago|reply
[+] [-] jwr|6 years ago|reply
I've seen it myself: a child would have no problems with loud music, but any kind of noise (as in, white noise) would be painful. This included hair dryers, vacuum cleaners, some power tools, and sounds of water/sea.
[+] [-] b3lvedere|6 years ago|reply
[+] [-] mindgam3|6 years ago|reply
Those devices are literally painful for me to be around. I view them as a scourge and will consider not washing my hands if there’s no soundproofed alternative.
[+] [-] minikites|6 years ago|reply
That's probably fine, air dryers make your hands dirtier than if you haven't washed them at all.
https://www.washingtonpost.com/news/to-your-health/wp/2018/0...
[+] [-] unknown|6 years ago|reply
[deleted]
[+] [-] chaosbutters|6 years ago|reply
[+] [-] greedo|6 years ago|reply
[+] [-] dmix|6 years ago|reply
I wish every ecommerce store looked as good and simple as that one.
[+] [-] Lorin|6 years ago|reply
[+] [-] Shivetya|6 years ago|reply
I know the professional dryer my mother uses is specifically designed to put out good airflow but does so with by using a slower speed but larger vane fan. the motor and input is near the user with a long exhaust tube exiting near where the dog is, they are always mounted to allow ease of movement.
[+] [-] jordache|6 years ago|reply
[+] [-] mauvehaus|6 years ago|reply
Many years ago, I actually had a desk in an office that was maybe 10-15 meters from a nearby Excel hand dryer, separated by two doors. I hated it with a passion. Every time somebody dried their hands, I'd hear it. I left that job for a lot of reasons, and the hand dryer wasn't exactly one of them, but I wasn't sad to be rid of it.
And I'm not 9. I'm 35. I find that I have pretty good hearing, at least as compared to my partner.
What gets a little weird is that since leaving software and making a career change to woodworking, I've gotten more sensitive to loud noise. I used to take the subway to work like many other people. Now, I find that the noise of the train is too loud.
I'm religious about wearing hearing protection in the shop. I don't know if my hearing has gotten objectively better, or if I'm just more aware of loud noise than I used to be. It'd be hard to do a study on that without a time machine though.
[+] [-] cglace|6 years ago|reply
[+] [-] userbinator|6 years ago|reply
Fans are loud, especially small powerful ones. There's plenty of other comments here complaining about the Dysons, and I agree; and I also much prefer the older ones (with a heater), which seem to have a far slower fan and a deeper note. That said, I find towels/paper most effective for drying.
But if insisting on air drying, perhaps a design with the blower elsewhere (maybe centralised, like a vacuum --- another fanned device that's also very loud), a local heater, and slower air flow would be more ideal.
[+] [-] lqet|6 years ago|reply
That being said, even I cannot stand the sound of hand dryers in public restrooms. To me, it basically sounds like an extremely hysteric hair dryer. I wonder if it has anything to do with the fact that they are mounted on a wall, which gives them more resonance.
[+] [-] __MatrixMan__|6 years ago|reply
https://ibb.co/mCNdGdh
There's no shower anywhere nearby, but this object which I consider to be obviously a hand dryer is labeled "hair dryer". Surely the people who make these know what they're for...
And I agree, a large tank of compressed air with an on-demand heater on the human end would be pretty nice.
[+] [-] bonestamp2|6 years ago|reply
[+] [-] aitchnyu|6 years ago|reply
[+] [-] jgalentine007|6 years ago|reply
[+] [-] adrianmonk|6 years ago|reply
Basically, the loudness of a sound hitting your ear is a combination of multiple factors:
1. How loud the sound source is.
2. How close your ear is to it.
3. How much it reverberates or dissipates.
Imagine if a hand dryer were installed outdoors in an open field. Sound would emanate from the dryer, then wander off never to return.
Now imagine a hand dryer in a room with carpet and some soft furniture like a couch. Sound would emanate from the dryer, and some of it would hit surfaces that absorb it. But some of the sound would also hit reflective surfaces like walls or glass, and that reflected sound could come back to your ear and increase the total noise level.
Now consider what a bathroom is like. For ease of cleaning, it's entirely hard surfaces. Concrete, porcelain, tile, metal, etc. These absorb almost no sound. And bathrooms are typically pretty small rooms. It's basically the worst case for taking an already-loud thing and making nearly all the noise reach your ear.
[+] [-] proee|6 years ago|reply
https://www.health.harvard.edu/blog/the-bacterial-horror-of-...
[+] [-] jasonmp85|6 years ago|reply
I think the simplest solution would be for municipalities' health departments to outlaw them, or at least set VERY conservative noise limits.
[+] [-] chousuke|6 years ago|reply
I'm not sure why they're so common given that they seem to only make things worse.
[+] [-] Reason077|6 years ago|reply
- Paper towels? Environmentally unsound.
- Washable towel on a continuous roller/spindle thing? Common in past decades, now pretty rare. Requires regular servicing. Expensive? [1]
- Don’t offer hand drying at all? Uncomfortable especially in cold climates. Might discourage people from washing their hands at all.
While I agree they need to be quieter, Hand dryers are still the best technology we have right now.
[1] The British Library still uses these in their washrooms, presumably because of noise concerns with hand dryers.
[+] [-] pwg|6 years ago|reply
Air hand dryer:
One purchase - zero daily maintenance needs.
Paper towels:
Continuous purchase expense (buying new stock) - continuous daily maintenance needs (resupply of dispenser), increased refuse expense (all the discarded paper towels increase the refuse stream size).
When you tally up the expenses for "air dryer" vs. "paper towels" for a busy restroom and over a reasonable time span (say 1 year) the cost differential is why air dryers are so common.
Of course, some owners also advertise the environmental aspects, but the true reality is the air dryer is there because it saves the restroom owner a significant amount of money each year.
[+] [-] dngray|6 years ago|reply
When I was little I used to be worried they would eat my fingers, particularly ones that looked like https://i.imgur.com/hCMAQV7.jpg with that little shiny metal dome. It kind of made me think it was hot and i'd somehow burn myself.
I wonder whether those super-fast ones (like the dyson airblades) are better or worse for children these days.
[+] [-] Spooky23|6 years ago|reply
With paper towels, you need to visit a busy bathroom a few times a day to empty the trash.
[+] [-] henvic|6 years ago|reply
Automated paper towels dispensers should be the rule, not some fancy air blade thingy.
If I'm healthy, it is also good for the environment.
I never liked hand dryers both because of noise and the risks of spreading germs. I'd only use them on a brand new restroom, then never any more.
[+] [-] merpnderp|6 years ago|reply
[+] [-] EADGBE|6 years ago|reply
"Patient Zero" doesn't usually exude symptoms until it's too late.
[+] [-] jawns|6 years ago|reply
That person should have a piano dropped on them.
It's awesome that this young scientist decided to investigate and call attention to this issue, and even better that she's resolved to help come up with solutions!
[+] [-] Havoc|6 years ago|reply
I’ll rather walk out with dripping hands
[+] [-] loginatnine|6 years ago|reply
This all makes more sense now, thanks to this kid for this, I've never realized how noise was different for kids.
[+] [-] darfikk|6 years ago|reply
[+] [-] b3lvedere|6 years ago|reply
My kids hate the Dyson hand dryers. These things are incredibly loud.
[+] [-] CriticalCathed|6 years ago|reply
We really should just mandate that public restrooms use Cloth Roll Towel Systems for hand drying. It's economical in the long run, not a giant waste of resources, and it is proven to be more sanitary than paper hand towels!
[+] [-] bryanlarsen|6 years ago|reply
[+] [-] ohazi|6 years ago|reply
[+] [-] afandian|6 years ago|reply
And yet, they're seen as a medium-high-prestige item.
[+] [-] dfee|6 years ago|reply
[+] [-] cbg0|6 years ago|reply
Pic for reference: https://www.savemoneycutcarbon.com/wp-content/uploads/Dyson-...
Edit: if you find the older ones disgusting, make sure to let the place of business know by complaining to them, otherwise they're never going to change them unless they break.
[+] [-] Reason077|6 years ago|reply
There is, however, another Dyson design where the hand dryer is integrated into the sink/tap. This one actually blows particles/droplets from the sink up towards your face, which does give me some hygiene concerns:
https://www.dyson.co.uk/hand-dryers/dyson-airblade-wash-dry-...
You can find these in some of the washrooms at Heathrow airport.
[+] [-] danielecook|6 years ago|reply
[+] [-] vbuwivbiu|6 years ago|reply
[+] [-] lquist|6 years ago|reply
[+] [-] trophycase|6 years ago|reply