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.
> sometimes kids have reasons for what they say or do
Raising two kids I've come to think that this is almost always the case. The reasons may be based on misunderstandings but they are logically coherent in the context. A lot of times they may have a hard time explaining it, especially when an adult loses their temper because they decide the thing is just a folly.
In my kids' school they are not allowed to wear shoes indoors, but my son refused to take his off and wouldn't explain why to the teachers. It drove them mad, and we got phone-calls and emails telling us this had to stop that he must obey the same rules as the rest of the kids! We spoke to him (without reproach) and slowly we realize that he knows his shoes are expensive (because they are pronation) and it turns out that someone had hidden them before. After we explain to the teachers he is allowed to keep is shoes by his desk as long as they are not on his feet. Problem solved.
It makes you wonder about how teachers are selected and trained in the first place/what kind of behaviors are incentivized that they would not be able to handle a minor situation like this and had to resort to emailing/phoning parents when all that was needed was to just sit down and have a calm chat with the kid.
I imagine teachers don't have the time to have this type of 1:1 interaction with the 25 students in their class. Seems like email/phone communication to the parents is reasonable here. Something like disciplinary action would have been bad though.
Interesting, thanks for sharing that link. I had a ton of weird tics as a kid which could easily be traced back to the large amounts of prescribed amphetamines I was forced to take under threat of punishment. The solution to the tics was... more punishment.
It took me years to realize things such as, the reason I would chew on my shirt color all day even though I would routinely get sent to the principal's office and publicly embarrased by teachers or beaten at home was just because my jaw would get very tense and chewing motions relaxed it, and my mouth was the Sarah Desert and sucking on the fabric pulled moisture into my mouth.
My shirts would be sopping wet in the front and would all have tooth holes from my chewing them, I'd go through a shirt a week nearly.
I wasn't on any meds but my teacher at the time would dole out punishments regularly to me in class. I've put 2 and 2 together before, but I never knew I wasn't alone in this behaviour! Thanks for commenting, this really helped me.
All those poor buttons. And then I come to find out that one popular tip for reducing dry mouth in dry environments is literally sucking on a button.
I wonder how common it really is in young children. Certainly seemed I was the only one dealing with it at several different schools. Is it too late to form a club?
Similarly, I had issues with scratching my nose in public, nail-biting, hair-pulling, picking at scabs, sucking my thumb at night... punished and beaten all the time for it, and some particularly nasty teachers would try to make a public example... come to find out in my adulthood that I have a literal disorder, body-focused repetitive behavior (BFRB) syndrome, which is related to OCD and bipolar disorder and ADHD which I also deal with, and heavily exacerbated and permanently worsened by my forced exposure to intense medication.
I still deal with BFRB and I've had a few instances of old tics resurfacing, but a combination of practice and learning much about my disorders and cognitive science has helped me tremendously with everything else, such as nervous tapping, twitching, repetitive audible excitations, speech impediments and the like. I believe even my BFRB will eventually no longer be a problem. They all subsided at different points in my youth, mostly after conscious effort.
When I was first placed on medication at five, I developed a pretty awful tic wherein I would swallow every five seconds. I was sent to therapy and the therapist first thought I was lying to get attention and then thought I was crazy and needed more medication. This tic was causing gastrointestinal distress, dental issues from lack of saliva, and was a major speech impediment for me. My esophagus would get pretty raw. This was my first experience in learning how to deal with these on my own.
One tic that seemed to go away without extended cognitive effort (on account of its lower frequency) was extended periods where I would laugh uncontrollably over nothing for half an hour or longer until I was red in the face and choking for breath and my diaphragm was convulsing. This lasted for a few years until adolescence. My family thought I wanted attention again and would punish me when I couldn't stop at their command. It's honestly insane how some people respond to behavioral anomalies in their children.
Thanks for your response. My son is 9 and he goes through phases of having some sort of tic (throat clearing, head shaking, blinking, etc). They're not too bad, relatively speaking, and no one has really noticed. Or if they do then they probably dismiss it.
His pediatrician said it's likely a mild form of tic and tourette syndrome which often goes away by age 13. We haven't brought it up to him besides once or twice asking if he feels any discomfort. We haven't talked to him about stopping the tics and don't plan to. I hope his classmates continue to ignore it and that they remain mild.
Sorry your experience was not supportive and I hope BFRB does, in fact, go away for you.
I would say that habits are everything, and in some cases, I believe even extreme disorders like schizophrenia can sometimes be caused by bad neurocognitive habits degenerating unchecked.
You're doing the right thing by not making a big deal out of it or making them feel different, but as your son gets older and more able to have these kinds of conversations, it's worth opening a dialogue with them about finding ways to form new habits that break the old ones.
Many of my tics only went away after much effort, and growing up I felt like I had no one to talk to about them. My family didn't understand and I didn't have good experiences opening up to other children about them because they also either thought it was an attention thing or that something was really wrong with me.
At some point your son is going to become stressed by his seeming inability to control his own body and he will want to have positive dialogue about it. He may not have the courage to initiate the conversation though or he may be worried you won't understand. I wouldn't approach it with a bag of tricks but rather learn together with your son and encourage them to pursue better habits when apt. I know for me, accepting my disorders as purely physical and maintaining the belief that I could overcome them mentally was instrumental in my healing.
Good luck! I'm sure one way or another he'll figure it out as long as he is surrounded by positivity.
One thing to remember is that sometimes it's correct to realy trust your kids even in contradiction to your best assessment of the situation. The hand-licking story is about tactics for diagnosis, but another angle is that (sometimes) it's OK to not understand something, to think your kid is wrong, but to let them have their way anyway. Missing a plane vs dirty hands? Trust the kid, find another solution (grab a towel, wipe hands on pants, take the germ risk, etc), and talk about it later as best you can.
You don't want to let your kid be the boss of everything; you don't want to let your kid ignore your intructions or choose to do something fun instead of necessary work, but if your kid would rather stand there and do nothing while getting upset instead of doing some small work item, they aren't "cheating" you out of anything by getting their way.
Kids have a reason for everything they do. If you don't know the reason, it's because you've failed to communicate with them. Sometimes they don't know themselves, but that's still a kind of communication failure.
There are many things my kids were saying that I only figured out days, weeks or years later. Listen, guide them, let them be, and don't be a helicopter parent.
The Kennebunk rest area in Maine was designed by someone who hates children or is utterly incompentent or both. The diaper changing table is flanked on both sides by 4 loud hand dryers. The icing on the cake is the solitary paper towel dispenser is located ABOVE the diaper table. If you drew the short straw for diaper time, you'll be treated with your child screaming for mercy from the dryer noise AND have people who prefer paper towels dripping their wet hands all over your kid.
I'm with the child on those tap dryers. They seem designed to blast any remaining drops of water in the bowl into your face or shirt. Hate the damn things and avoid them now. Maybe the places were using the wrong bowl or something. :)
I saw these for the first time on monday. The first thing they did was blast all the water in the sink into a fine mist and spray it over me. I can't believe that the people who designed or specified these ever used them.
Oh the pathos! If only they had known of the "Six Step Reframe" algorithm (which is actually deprecated now in favor of even more effective algorithms.)
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.
The cone cell of the human eye is the main type of photoreceptor that senses differences in light bandwidth, aka color. The dics of the cone cell are tuned to be receptive to certain bandwidths of light. These bandwidths are well understood and do not change as humans age (outside of damage to them)[0]. Humans only have 3 sets of these cones and do not gain or loose new types of cones as we age. The receptive bandwidths of the pigments are set by the biophysics of the molecules.
The perception of color does change as humans age, however. Typically, a newborn cannot yet use their eyes well. They can percieve light and dark, then red, then they can process depth, etc. This learning process takes a few weeks to months[1].
The cognition of color is a very in depth and facinating field. Thus far, it appears that color is a cultural and learned thing, in that if your language does not have a word for a color, it seems to be very difficult to determine the color as a different one from among other colors. Translating the mix of photons that your photreceptors are affected by into usable language is a very complicated process and is not well understood yet.
Fun Fact: The Illiad does not include the word blue and the Bible uses it very rarely as well.
Also, we hear using the cochlea, a spiral sense organ that sorts sound by frequency. In children the whole thing is much smaller. So they hear much-smaller wavelengths of sound which means higher-pitched sound. As we grow so does the cochlea so we hear lower and lower sounds and lose the sensitivity to the highest-pitched ones?
I'm guessing that hair dryers have a scream in the upper register that adults don't normally hear.
That's very possible indeed. I remember when I was a kid my grandparent's tube TV was making a high-pitched sound that was figuratively driving me insane (maybe generated from the HSYNC frequency, now that I think about it). I couldn't understand how they could bear it but of course when I told them they didn't get it because it was probably way outside of their hearing range. I'm fairly sure that now that I'm in my 30s I couldn't hear it either.
> The Mosquito or Mosquito alarm is a hand wound machine used to deter loitering by young people by emitting sound at high frequency, in some versions so it can be heard mostly by younger people.
> The sound was made into a mobile phone ringtone, which could not be heard by teachers if the phone rang during a class.
At 35, I'm still deeply bothered by that sound. Slightly related but in a lot of parts of Ginza in Tokyo, they use a similar sound for repelling rats that I find extremely uncomfortable...
Typically a high-pitched whine from a CRT is from the flyback transformer. I found, when I was a kid, that sometimes a well-placed whack on the CRT's cabinet could temporarily fix the problem.
Nowadays, I have no idea if I can hear that whine anymore or not, as CRTs are quite uncommon. Probably not. Much for the better, as it used to give me headaches.
15Khz colorburst whine. Its amusing how many audio recordings even today show a notch filter used at that frequency, years after there were no CRTs anywhere in the recording process.
I was quite surprised as a young adult when one of my ears couldn't hear cricket chirps anymore. If I laid with one ear against the pillow I could hear them, but if I turned over it was silent. A hearing test confirmed that one ear was deficient.
The dimensions of the cochlea are basically fixed at the time of birth. As the dimensions of the cochlea are the main contributing factor in what tones are able to be heard, the tonal bandwidths are then set at birth as well (minus hearing loss due to damage as we age). If you are interested in how sound is interperted by the brain, be aware that it is not a straightforward process and takes a bit of research. Still, the cochlea is essentially fixed at the time of birth.
Does that mean that children also don’t hear deep bass? Is it commonly accepted that young children don’t enjoy the sort of music (e.g. dubstep, drum-and-bass) that employs near-infrasonic notes?
An other thing to consider with deep bass is that, at least in concert/club conditions, you feel the bass with your body on top of hearing it. So even if your ear struggles to capture those low frequencies you'll still experience them somewhat.
Even as adults, you feel anything below 45hz or so more than you hear it. I am confident that children feel too. But the bass heavy club music ypu describe has an adult cultural element, otherwise missing from most music.
I'd be interested in hearing more about this. I understand the mechanism whereby audio sensitivity is progressively lost but I don't see why getting older would result in seeing fewer colors. Is this perhaps instead that we are less sensitive to color, requiring more photons to have the same color experience, but not actually seeing "fewer colors" in the sense that there are colors that fall off our gamut entirely? That would make sense to me.
discrimation (horizontal) vs sensitivity (vertical)
As we age, we lose some hearing power and visual acuity, for physical reasons on the organs.
As our brains mature, they learn to not discrimate among certain "unimportant" sounds and colors. Adults can't lose the ability to disambiguate among novel language phonemes from foreign languages (as perfectly as kids can), and similarly they lose ability to distinguish similar colors that they learned are irrelevant.
This isa tradeoff adaptation, so you can see a shadow gradient as single color instead of a complex spectrum, understand that traffic lights are showing the same signal despite variation in frequency, etc.
On another level, very small children (babies) have poor color vision, because their eyes and brains are still missing basic development.
So it's a curve: newborns have poor hearing and vision tha rapidly improves for a few years and then decays slowly, for both physical breakdown and for mental "optimization"
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.
Agreed. Luckily there is a small delay between pushing the button and it actually flushing. I usually press the button and then cover my ears until it stops again.
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.
The Dyson combined tap-dryers are awful, awful products - we have some in newly fitted bathrooms at my workplace. I don't know how they made it out into the world without shame. They're hard to trigger reliably, they blow water everywhere, they're generally cumbersome and unpleasant to use.
That's amazing. In a 2 minute promo video with many clips of people washing hands, and many clips of people drying hands, they never show someone washing AND drying hands in the same clip. They know the poducts doesn't work at its primary value-proposition.
I swear by their vacuum cleaners, but none of the Dyson hand dryers are good. The boxy air blade ones are the worst I've used so far, but I haven't seen the tap ones yet.
We have one and it is like trying to drag a tank around the house into small spaces. Like all Dyson products, it's cleverly engineered and presumably hasn't once been tested with an actual customer.
Their stick vacuums are light, although the battery life is short. They are quite effective but only if you use the right head for the job. There is one head for carpet that is amazing for carpet, but it's terrible for hard floors. There is a head that is great for hard floor, but obviously terrible for carpet.
I love the stick vacuum for cleaning stairs, it's far more convenient than dragging a full size one up/down the stairs. Agreed that the battery life is too short.
I was in Japan recently and they didn't have the Dyson one but they had very similar models from Panasonic and Mitsubishi and they were much quieter and somehow worked better. We need those.
I haven't seen one of those Dyson pieces of shit without at least some gunk or water sitting near the bottom, not draining or sliding into the airflow. Even if you get everything off your hands, having a stupid plastic device with a deep crevice in an environment with fecal coliform presumably floating around is a _great_ design let me tell you.
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 always think they should just take it down and put up a sign that says, "Too cheap for towels." It won't damage my hearing and will get my hands just as dry.
No, it doesn't. We should be (and AFAIK often are) at the point that paper towel pulp is coming from forests we replant. Also, I don't know, maybe those dryers "save trees" but the paper towels provide a forcing function for someone to always have a couple of ready forests on hand, which seems better?
Yeah, I just don’t buy it. 100% recycled paper towels are a thing. And if you really want to get technical it seems like manufacturing and using those devices consume far more energy. Anyway, glad I’m not the only one shaking my head at these things...
Honest question: Have you tried just vigorously shaking your hands and then letting them air dry? It only takes a couple minutes. Worth the wait to still have clean hands.
Honest question: is there anything about my comment or profile that suggests I’m open to receiving hygiene suggestions from a complete stranger on the internet? It’s not like I don’t know how to have clean hands, just saying.
>is there anything about my comment or profile that suggests I’m open to receiving hygiene suggestions from a complete stranger on the internet?
It's probably that you're participating online in a discussion about hand-dryers, and, by proxy, washing your hands -- and expressing your disinterest in using them (hand dryers) .
It might even be the fact that you've said that you considered not washing your hands all together when posed with no alternative -- a danger to others besides yourself.
I find your tone to be entirely unwarranted and rude.
Actually, it was the part where you stated you considered not washing your hands? And I was honestly asking because most people don't realize how quickly human skin dries. I hate air driers also, but I generally don't use paper towels anymore either unless I'm planning on needing dry hands within a minute of leaving the restroom.
Or, hey, we could go with your interpretation that I'm a raging asshole that thinks you don't know how to wash your hands. Whatever floats your boat.
Sorry. I assumed I was being trolled and reacted accordingly.
I was being ever so slightly hyperbolic in my statement about not washing hands. For the record, I do use the time-honored air-dry, shake-hands-vigorously and/or dry-on-pants methods when circumstances demand.
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?
I got started taking a basic hand tools class and followed that with other evening and week-long classes. I'm actually not somebody who's been in the shop since they could walk; I'm pretty late to the trade.
At the moment it's like that old joke: "What do you call a drummer without a girlfriend? ... Homeless." I do make some money on commission work, but not enough to cover my living expenses. What I do make I'm largely investing back into the business, which I just started. This is probably fewer tools than you might think; I pay for annual access to the bigger tools I don't have, and I have a pretty decent selection of the moderate-sized tools that I got for pretty short money (band saw, drill press, and table saw. All good tools, total: <500 USD).
Mostly it's stuff like a camera and lights to shoot my work, a logo, and the other sorts of things that separate a hobby from a business. A better website [0] is on the list as well, but never having been a web developer, my partner and I are likely going to use squarespace or something similar.
Am I glad I made the switch? Emphatically yes. I love the woodworking aspect. I'm happy to report that my partner is helping with the business-y things. Also: she's a way better photographer than I am. Any of the pictures on my existing website that look good are probably hers; the crappy ones are mine (and need to be re-shot around the time we get around to settling on a logo and commit to getting a real website up).
TL;DR:
I'm lucky to be married to the world's most supportive partner.
[0] http://longwalkwoodworking.com <- HTML like it's 1998, CSS lifted pretty much straight from the "68 bytes of CSS..." article posted here a while ago. There really do need to be pictures on the home page, a contact page, an about page, etc. Hosted on github pages, no Jekyll, etc. I threw something up so that I could put a URL on business cards and have it go to something.
Holy crap. This may seem weird, but I've been looking for boxes. I've got way too many small things that don't seem right in the open, but also don't have purpose built containers...
If you're interested in making a few I'd love to buy a few veneered boxes ( in the pictures presumably taken by your wife ;P )
...For real, I have a primal need for boxes that don't feel threatened by a stiff wind or a few ink wells stacked inside...
Thanks! I'm still working on getting the dovetails perfected. Like a lot of things, they require practice. While I usually get them right, if I haven't cut any in a while, they often come out a little rough until I get my hands used to making the right motions again.
Really perfecting them would mean getting them both accurate and fast. I definitely need to cut a few more to get to that stage, and do it regularly to keep it there.
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.
My parents used to use the vacuum cleaner to put me to sleep as a kid, even into my toddler years.
One night they forgot to turn it off and the motor burnt out.
To this day, I sleep (and often concentrate) better with some white noise going - turning on the bedroom fan is an essential part of my night-time ritual. There's some evidence that loving white noise is linked to ADHD, but I don't think that it's predictive for a 4 month old. :P
Newborns like loud environments. A birth changes environment for child from very loud to a very quiet. I suppose it feels like sensory deprivation for a child. Seems that hand dryer reminds your daughter a good old times before her birth.
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.
For what it's worth, I've seen (and used) those in gyms and bike lockers at offices as a hair dryer. It's possible the person/company who bought it and installed it did not know what they were buying.
I don't know that there's really any difference between this and a hand dryer, but I've certainly used them as hair dryers too.
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.
One of my great joys in life is how much my daughter loves my stubble. She grabs my face with both her hands and declares “Sooooo scratchy!” and then squeals and laughs when I nuzzle her cheek with mine and pretend to be a horse. From ~3 yrs old, now going on 10.
My heart will definitely break a notch if the day ever comes she outgrows that!
She may outgrow it, but she'll probably never forget it.
I'm a guy, but I recall as a kid feeling my dad's stubble when I gave him a hug as a child, when he came home from work, smelling of sweat and tar (he worked as a road maintenance worker - a very hard job, especially in the summertime in California).
He passed away 14 years ago, and I'm turning 46 in a couple days; how time passes...
Same here. My strongest sense memories of my dad are the feel of his shirt against my cheek when I'd run up to hug him when he got home from work, the feel of the callouses on his fingers, and the stubble on his cheek under my hand.
I remember those things more often than I do the sight of his face, or the sound of his voice, or the smell of his cologne. By far.
Is it just my kids then that seem absolutely immune to cold water and will happily jump into unheated swimming pools, and will happily have a cold bath?
I noticed my boy was happy getting into cold water as a toddler (compared to adults who suffer during the transition from air to cold water).
Now he's four years old, and a few weeks ago we swam together in a cold lake. He was happy to get in, but after ten minutes I noticed that his teeth were chattering and his lips were blue, while I was quite comfortable.
Having been a cub scout leader and now a parent you see that kids don't really have a great sensitivity to their own body temperature. They'll wear hot coats in Summer and tshirt in Winter unless you tell them not to, they're usually pretty far gone (sunstroke/hypothermic) before they will realise for themselves that there's something wrong.
I don't think they really get a good idea until they are about a year in to puberty, and even then they're more prone to mismanage their clothing (but I think that's just experience).
Also worth bearing in mind that younger kids have higher body temperature, and that they usually have lower surface area:volume ratios than bigger people.
There are two dimensions here -- one is that they may not feel it at all; the other is that they may feel it but not realize it's bad until it's too late, and might not attribute cause.
For example, going out in the cold doesn't hurt at first, but the pain builds up. As an adult, you may react to the initial no-pain sensation because you correctly predict you'll be freezing later.
Also consider that as an adult the same feeling can be both good or bad by mental context: consider a warm toilet seat -- warmed by a fancy Toto heater at home vs warmed by a stranger's buttocks in a fast food bathroom.
I was like that as a child. As an adult, I’m always hot, unable to live without air conditioning, always looking forward to cooling down with a swim or a cold shower. (And I live in Canada; it’s not like the ambient temperature is all that high!)
Maybe I was that way as a child as well, and just wasn’t introspective enough to notice.
As an adult, I do get cold eventually, though; I can’t stay in cold water for hours, like I could as a child.
I think in this case it has more to do with that kids (and younger people in general) can hear better and at a broader frequency spectrum. I (and I know other people with the same problem) for example am always irritated why induction cooking plates make such painful noise but as most people cannot hear them, industry gets away with that. Same for those ultrasound devices to protect cars against martens that can get as loud as 200 Db.
I guess they're referring to things like kids running away from distant relatives who want to kiss and hug them, which is definitely something that happens.
That's definitely part of it, but I think (and I also remember) that a part of it is that children have a well-developed sense of personal space and who they are close enough to for different types of contact, from a pretty young age, but their sense of closeness is (quite reasonably) derived from actual (remembered) contact rather than from having a genetic relationship or contact before they can remember.
We have to remember that kids don't have any reason to love distant relatives, and that adults don't have the right to demand physical affection from kids.
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 recently learned that (at least in the US) those loud motorcycles are actually illegal, and that it is near-standard practise that motorcycles are sold with cheap but compliant mufflers which everyone knows (wink wink) will be replaced with aftermarket loud (but illegal for road) mufflers.
I applaud the research of this young student, showing that noise pollution is not just a nuisance, but a real health concern. Young ears getting permanently damaged is one aspect. Entire neighborhoods losing nights of sleep is another.
When a loud motorcycle [0] goes though a city at night, I wonder how many people it wakes up. It could easily pass thousands of people with just a few miles of driving. If 1% are woken up, it could still cost dozens of total hours of sleep.
Based on how much a loss of sleep lowers performance (and increases health risks), the total cost of that one motorcycle driving one night might be huge. The cost of the health damage and lost productivity might be about as much as stealing a car.
Since the cost is spread out over a lot of people, we don't tend to care as much about it.
[0] Likely with the muffler deleted. While technically illegal, no one enforces any laws related to the noise output.
Not sure why you're getting downvoted here. In Brooklyn and Queens, this happens a ton. If a loud motorcycle happens to rev when you're on the street, it's viscerally terrifying.
Sure, that's why open pipes at three AM are run full throttle in second gear on a city street with thousands of houses. It's simply narcissism.
I had the pleasure of living on Overtoom in Amsterdam, which is a beautiful street but I'm a relatively light sleeper and even at the back part of the house you'd be woken up several times every night by some 'look at me' dude making as much noise as possible. Not a car pulling out in sight at that hour.
This is the same tired excuse my friend made when he got a loud bike.
It’s just not true. He later told me he enjoys the feeling (vibrations) and that there was something primal about “taming” something that sounds powerful.
As for car drivers, you should be assuming they can’t see you. Driving defensively is the only way to stay alive and you can argue that it shouldn’t be that way but it doesn’t make it any less true.
Modern cars are so sound-insulated that the volume of the motorcycle isn't going to have that much of an impact in normal operation. Fit a louder horn to the bike if you need to draw attention in specific situations.
Loud exhausts are definitely not designed to make motorcycles more noticeable to cars.
I ride and do "feel" the sentiment that loud pipes might help in some situations. But here's a rider-centric article that helps address the situation _and_ provide some actionable advice.
Thanks, that article makes lots of good sense. I see more and more riders (on relatively quiet bikes) drive with high visibility gear, especially on the highway, which is great.
But those are rarely the 'loud' types, they're just people using their bikes as transport rather than as an attention seeking device.
For example, Washington requires testing in part of 5 counties (out of 39), for non-hybrid, 4-wheeled vehicles older than 2009. But even that is misleading, as the emissions testing program is being discontinued entirely at the end of the year.
So even if they wanted to just add noise testing (it sounds so simple!), most cars don't get annual testing, and in another 6 months, none will. The state won't even have facilities for it.
The bigger issue I see is that emissions is generally seen as bad by everyone. Most people don't spend money to mod their car to pollute more, so if you test cars once a year, it's probably going to be OK the rest of the year. People do mod their cars to make more noise, though, so if you test once a year, they're going to fix the noise for the test, and then put it back the next day.
To fix this problem, you need to be able to catch people on the road.
I didn't realize how tragically limited emissions testing is (everywhere I've lived in the last 37 years has required it.) After some cogitating, I think you're right about enforcement needing to be done on the road which is unlikely to ever happen.
I was thinking something a bit more simple like a smartphone with a directional mic and opencv could work - at least for getting an idea of the scope of the problem. Put one on each side of a two lane road and you could probably get accurate results.
It's not 50% unless you live in a tight-knit ricer neighborhood. It's not a trivial option to customize a car to make it louder; it takes a bit of effort.
What is true that we tend to notice annoyances more than non-annoyances, and that the car may be louder because the driver want to accelerate or velocitate more than they should, and noise is a side effect. Or the stereo is louder than it should be, not because they want you to hear it, but because they want to hear it and they don't care about you.
My observations are a bit different. I live in a populous suburb (150k residents?) north of Denver. Truck culture is very prominent here and mainly consists of raising a vehicle and making it louder - mostly because they do want to attract attention. My 17 year old neighbor modified his Subaru so that it can (literally) be heard from miles away - and when he simply turns the car on can be heard clear across the entire neighborhood until the engine warms up and throttles down.
I'm not so much annoyed as I'm curious as to how all of this noise affects the environment at large (people's sleep quality and mood, birds migrating, insects mating etc.)
It can actually be extremely trivial and cheap by just drilling holes in your muffler (yes, I've seen this). Or by installing a glasspack for ~$20. This is what everyone gets annoyed at, usually.
I'm surprised that making sure noise output is sane isn't a standard part of certifying stuff for human consumption, but then I guess that's the whole "free market will sort it out" idea not working as expected. Nice to have work like this to say that maybe it would be a good idea :)
It isn't just the "loud" noise, either. There's a giant white and dark grey yacht parked in the Vancouver Harbour about half of the year. (It's the one near Jimmy Patison's yacht, except at least twice as large and probably modelled after a Star Destroyer). I have never seen it move, but as long as it is there, it emits a low-frequency hum that causes noticeable churn in the water over a ~150 meter radius. It is like a giant, evil subwoofer of the unreasonably rich. It's frustrating to paddle anywhere near it, it gives me a headache, and I can't imagine what it does to animals that share the water. Whenever I'm near it I'm bothered that the thing is allowed to exist, let alone park there.
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.
I refuse to use the Dyson at work for precisely this reason, and I try to not be there when other people do - our bathroom is a rather small confined and reflective place.
I find that Dyson makes some of the quieter hand dryers I've encountered, although maybe that's because they tend to be in larger restrooms. Starbucks really hurts my ears with much older style hand dryers in their single-occupancy restroom.
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.
Most environmental health regulations (all the ones that I know of, at least) forbid the use of air hand dryers in restaurants and public kitchens, instead requiring paper towels. That should tell us something.
Just don't touch is a tall order with Dyson hand dryers. They are fundamentally hard to use correctly because of tight clearances.
The way they work is based on the idea of a narrow stream of air that gets water off your hands better. But for the stream to remain narrow and not dissipate, you have to get your hands close to the equipment. It's based on almost but not quite touching it.
Positioning your hands in a careful and controlled manner is, ergonomically speaking, an uphill battle. So on average, it won't happen often.
In other words, Dyson hand dryers kind of trap you into accidentally touching the part you don't want to touch.
Worse, the same applies to all the people who used the hand dryer before you. It's a very reasonable bet that the surface where the air comes out has been touched by someone who didn't use soap when they washed their hands.
I can't say I've ever experienced this issue with the air blades. They seem easy to use them without touching any part of the hand dryer. I'm surprised that people have trouble with this!
Are you some kind of superhuman? Even if you try really hard and aim precisely, as soon as the air turns on your hands get pushed to one side because the pressure is not exactly the same in both sides.
Weird... maybe they are different where you are? Older models, or not installed/adjusted correctly?
I use these all the time (they’re pretty much everywhere in the U.K.) and haven’t experienced this unbalanced pressure issue.
They always seem pretty much equal pressure on each side to me.
With large hands, there's an extra degree of difficulty to avoid touching the sides and the bottom. It still leaves you with wet wrists and damp fingers.
An interesting study, but I wouldn't read too much into it. Who's to say that paper towels don't collect and deposit just as much bacteria onto your hands?
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.
Paper towels are recyclable and made out of recycled paper, at least. They are the most hygienic solution out there.
I still see the towel rolls around, they're a good option as well. Maintenance for (esp. public) toilets is never not going to be a thing, but it does require a bit more infrastructure to maintain (= washing out etc). But there's companies that will take care of that.
Not offering hand drying is the worst; drying your hands is arguably even more important than washing them when it comes to hygiene.
Anyway beyond that, fixing the hand dryers is also an option. Use larger but slower rotating fans. Dyson's machines have the problem that they have relatively small, high-speed motors.
They're not recyclable. If they're made from recycled paper, their fibres will be too short, like tissue paper or toilet roll.
On top of that, people might be using it to wipe anything, which could potentially ruin the rest of the recycling.
If you're putting any of that into your recycling, you're doing it wrong.
Also, do not recycle any paper/cardboard with grease or food contamination, especially pizza boxes with grease on, they will also ruin a recycling run.
> If you're putting any of that into your recycling, you're doing it wrong.
Hence the main problem with recycling. No reasonable person can know all the rules about plastics, what kinds of papers, etc. Why can't sorters sort it all out? Because nobody knows what to pre-sort.
Oh, come on. If you're capable of navigating normal life, you're capable of recycling. What you're saying is that you won't spend five minutes absorbing a one page document.
Recology has probably the most complicated arrangement I've had, and, well, this is not exactly rocket surgery:
Nice. What puzzles me is fast-food places with 3 bins (compost, recycling, trash) with these pictures on each -- when instead the pictures should be of the actual containers/wrappers that the restaurant uses. Wouldn't that be more helpful?
"that" in this case is the sort of things one finds in a bathroom. I don't think a reasonable person would think they ought to sort human waste with recyclable paper.
We used to have those everywhere in Vancouver. Unfortunately they got rid of them because teenagers were daring each other to strangle themselves unconscious using those things, and several people were badly injured or died.
I feel your pain too well. So many good things we could have in society, but due to a small minority of people ruining it for the rest of us.
Another poster mentioned that their child's high school didn't have any paper towels, which I can only assume is because the kids were wetting them and throwing them around the bathroom ceiling and walls to make them stick, which is something even I (regrettably) took part of as a middle school child.
Maybe I'm filthy, but I've always just patted the back of my shirt unless I'm in a place with clean cloth towels available.
It's not the outside temperature that'd discourage the already apparently slim number of people that do bother to wash their hands. It's water temperature. And if the water is freezing, no drying method will get the average joe to endure the pain of water hitting their hands.
I'm a proponent of cloth rolls. Toilets need regular maintenance anyway. Perhaps an air blower would function as a backup, but I'd honestly prefer drying my hands on my clothes, since in my experience air dryers are either ineffective or in the case of air blade systems so nasty that I don't want to go anywhere near one.
Yeah, it always annoys me when it's impossible to splash water on my face and dry it (perhaps I am a uniquely sweaty mess, I dunno). With most dryers you have to make some sort of cup shape to rebound the air into your face, and that's if you aren't instantly thinking of all the germs blasting out.
While I was at uni just few years ago all bathrooms had the towel on the roller. The main issue was that by the end of the day the entire roll has been used so you either re-used the same final patch of the towel that everyone already used, or don't dry your hands. Otherwise, great idea.
I don't see why these paper towels would not be 100% recyclable or that much different to regular toilet paper. Also, what if people would like to wash other body parts that can't be put in an airblade e.g. face?
I'm not sure why you're being downvoted, I mean I know why people are but I don't think they should be.
You're forgetting that we have to create paper towels/toilet paper, etc. from trees. And we aren't just talking a few trees, it's a deforestation issue.
Sure we could replant trees, etc, etc, but it still destroys the current eco-systems living there.
As long as they come from farmed trees and wind up composted, they're actually sinking carbon out of the air. Maybe it's not a net win because of the energy used to create them and move them around, but towel itself will lock its carbon in the soil for quite some time.
Live in the cold climate of Canada. I dry my hands by slapping my pants when I walk away from the sink. Then again, I also eschewed towels for the longest time in favor of slapping myself dry after showers
> 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.
The "zero maintenance" is part of the problem. Any hand dryer should have an air filter, and that air filter should need to be replaced frequently considering the nasty things that happen in that room.
> 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'm most concerned with touching the handle/door with a bare hand. Too many people don't properly (or worse, at all) wash their hands after using a restroom. Therefore, I stick with the paper-towel grab.
The step-handle is a nice solution to this, sometimes.
I almost always wait for someone to open the door if there's no way to do so without touching nasty door handles. Or find a tiny piece of paper to use and discard afterward. Or hold the door with my feet while I clean my hand after opening the door with it, if possible. When I go to restaurants sometimes I carry a paper napkin if I have been to the place and know it's complicated to get out without touching anything. Yeah, I'm that paranoid with it...
* Heck, I even change clothes when I get home before seating in my bed or sofa.
People won't touch the restroom door handle, but they'll touch every other surface in the facility without a second thought. Walking through a bathroom door doesn't magically make hands clean. The good news is if you have a healthy immune system you can touch anything, including the bathroom door handle and you'll be fine.
If I'm wearing long sleeves, use my shirt sleeve; if I'm wearing short sleeves, grab the bottom of my shirt and use as a glove. I've seen too many people drop mega-bombs in the stall, sound like they're making a hash of the cleanup, then explode out of the stall and walk right past the sinks. Why would I wash up just to get feces on my hands from the door handle?
Please use the paper towel grab. Don't disrespect your shirt like that, which will still be on you wherever you go the rest of the day until you change it.
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!
Not to mention studies showing that hand dryers, with the Dyson models leading the pack, do an excellent job of distributing bacteria over a large area.
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
I feel the same. I dry my hands on my trousers and wear headphones in the toilets to avoid the blast of white (?) noise from other users of the high-speed dryers at work.
It wouldn't surprise me if the UK regulations on these devices also only measure the noise levels without hands in the airflow... there's no way these are legal when they are actually in use.
Don't know why you are being downvoted, but at my gym I go through the same situation. Whenever I go into the change room/washroom, I go to the locker furthest from the dryer, meters away from it. It doesn't really matter since every time someone activates it, it sounds as if it blowing right next to me.
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.
The motion activated ones go off when you move a little, not when you stand up. I've had them go off twice while trying to go, then not go off when he was finally done. It is not pleasant to have a toilet flush under you.
If there is anything to hang it from, a long strip of toilet tissue, hung down in front of the sensor eye, generally prevents this effect of premature flushing.
I'm in exactly the same boat. To be honest, I've started to get twitchy whenever anyone uses one when he's NOT around, I'm that used to watching out for them.
Hand dryers. Leaf blowers. Hair dryers. Hoovers.
But bowling alleys and swimming pools are fine. I really want to figure out the spectrum of noise that hurts.
I've been sensitive to loud noises (still can't drive with my windows down) since I was a kid, and I've been diagnosed by a doctor to be on the spectrum (albeit high functioning) for various other reasons as well.
It's obviously different for everyone, but for me it comes down to a few things:
* Generally the higher pitch noises are way worse then a low deep "growl"
* Sudden, high decibel noises, especially if they're unexpected are BAD
* High decibel repetitive noises (ever have only one window open in your car on the highway and hear a WOMPH WOMPH WOMPH sound?) are unbearable.
* Restaurant buzzers, alarms, etc. Even the alarms coming from inside McDonalds while I'm in the drive through make me uncomfortable/
* Anything shrilly, no matter the decibel.
Sounds that are lower pitch, and continuous are much easier to get used to. The AC kicking on is uncomfortable, but after ~30 seconds the fan noise doesn't bother me.
For me public places have an "ambient sound" that seems to get filtered
out okay. Mostly only the occasional small child skrill bothers me. I also have social anxiety so I'll get uncomfortable anyway however.
----
This seems to align with your observation that bowling alleys/swimming pools being okay. Most of the sounds are lower pitch, continuous, and most of the sudden noises are expected (kids splashing, bowling ball rolling, etc.)
The biggest difference is the decibel level though. Hand dryers. Leaf blowers. Hair dryers. Hoovers, are all LOUD.
Imagine your parents SCREAMING AS LOUD AS THEY CAN AT YOU. That's how those feel.
---
I have a feeling my observations will apply to most people on the spectrum, but you'd have to multiply it by 10x/100x depending on the severity of the individual.
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 think I’ve read somewhere that Sir Dyson was pro Brexit because of strict EU regulations. They moved their HQ to Singapore so it’s certainly not about the UK.
We have a set of kid sized ear-guards that my son prefer to wear when I vacuum with my Dyson vacuum cleaner. It's extremely loud and very srill (but it's also very effective).
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.
I’m sure mold grows in there because of the constant dampness. You can’t avoid touching the sides because the airflow is so strong and kind of forces it.
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:
Soap and water does not fully kill the hand bacteria (which is good, kind of). And there are definitely possible problems with bacteria from those air dryers, see https://www.health.harvard.edu/blog/the-bacterial-horror-of-... - though there seems to be no real consensus here.
i am a bit confused by the problem here. if you decide to wash your hands and your face don't you get the same germs still on your hands onto your face?
if that is a problem then isn't the solution to wash hands more thouroughly?
on a side note, what concerns me much more is how many places i have to touch in a bathroom before even getting to the sink and start washing...
There is no need for cursing on HN. Yes, the older models of Dyson Airblade were noisy, but they have addressed this in the latest model Dyson Airblade V HU02 which is significantly quieter.
Also, why are germs on your hands after washing them? Surely you used soap which killed 99.9% of germs and given that the Dyson Airblade V blows air downward, you would need to contort yourself to put your face below your hands ...
Dyson hand dryers blow air literally everywhere. And it’s not necessarily my germs it’s blowing, it’s the accumulated germs of everyone who’s used the dryer before me and touched the sides/dripped water into the unit.
Strong language is fine on HN as it is in adult dialogue generally. It is often very effective at conveying emotion and emphasis, which was the case here.
The HN guidelines prohibit personal attacks and political or ideological battle (which includes attacks or inflammatory commentaries on gender, nationality, race, etc).
But using a curse word to convey strong displeasure towards a product from a giant corporation seems fine to me.
This seems to be a funny problem among some people, which also censor and beep each swear word in videos on YouTube or anywhere else. Seems to be some anticipatory obedience that is deeply embedded in some cultures/people.
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.
I have very hard time to believe this. It can't be helpful to drive people away -- at least I don't use any hard driers anymore because of their noise levels.
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.
Occasionally I'll check on how loud something is with my smartphone, and i'm always amazed at how loud some everyday things can get... especially when you factor in enclosed spaces.
So if I'm interpreting this right, solution 1, use towels for your kids if you can and solution 2, if there are no towels, hold your kid up and away so they are above the exit point of the air.
The Dyson blade driers (and their copy cats) are off limits to children anyway - they are not nearly tall enough to position hands inside them from above.
I've used them a lot (used to work for Dyson, though not on the driers) and I'd say the taps are actually one of their best products. Have you actually used one?
i just let my hands dry naturally, and teach kids to do the same. as long as it's not freezing cold outside they will dry soon enough. it's the most environmental friendly too.
So you're the guy who gets the bathroom door handle wet, causing me to use twice the resources to wash my hands again, plus extra paper towels if available to dry off the handle.
nope, see my other replies, not touching the door handle with wet hands. if there is no way to get out without touching the handle i'll dry off first. i just won't if i know i can get away with out touching anything for a while
How valid is it to make a sound measurement in direct flow of air? I am not surprised that blowing air directly in to sound measurement device causes high reading, but is the tool designed for that. Isn't it the same as saying that pressure washer causes x decibels of noise when directed in to ear? Both will probably be damaging or unpleasant.
She measured sound levels at the ear, not in the airflow. She specifically mentions children being shorter and likely to stand closer to the noise source, and so made readings at multiple distances.
Interesting, I have actually noticed that some hand dryers are uncomfortably loud, especially the "special" high powered ones. Combine that with the struggle trying to activate the dryer, and keeping it activated while trying NOT to touch the surfaces, I can understand why some kids seemingly does not like them.
I damaged my right ear-drum on a short-haul flight 20 years ago. I find hand-dryers almost painfully loud, and they rattle that ear-drum in an unpleasant way. Have often thought of doing dB measurements. Way to go, kid!
I can't stand anything past about 80db and I absolutely hate these things. Worst part is that there's no way to turn them off once they've been activated.
I would never consider using one of these. The annoying thing is when someone else walks into the bathroom and turns it on. Same for the disturbing, toxic – scented hand soap that is found in most bathrooms.
Out of interest, do you have a high sensitivity to noise around you?
I don't live in a particularly big city and when I visit bigger ones I do feel they are noisy. But not noisy enough to wear protection. I do wear protection when I'm on my motorcycle or at a concert or festival.
I can get by without protection, and it's not as though it particularly hurts; but I prefer things quieter, and it improves my mood. I often also wear it when I am working in an office environment with loud HVAC, also improves my mood.
I don't really know what would qualify as high sensitivity.
I have loud children, but they don't actually reach 110dB. I mean, YMMV, but I'd notice if there was something literally as loud as a rock concern in my basement or backyard.
Sure they do. I did a quick search and 110-130dB comes up on every result.
It's all about where you measure from, due to the inverse square law. For measuring things such as speakers for product specs, the standard is to measure from one meter away. But for rock concerts and hand dryers, you measure from the typical listening position.
I think you are considering your typical listening position for your child differently from the search results I found. If you were giving your kid a kiss goodnight and they screamed, it would be louder than if you were in the audience of a rock concert (but not louder than if you were kissing the concert speakers).
Every time you double the distance between the source and the meter, the meter reads 6dB lower.
Minor factoid: While that’s true in the limiting case (far away) for rock concerts, it’s common to use line arrays which fall -3 dB when you double your distance, as long as you’re within a certain range. Within this range they follow inverse rather than inverse square.
Very true. Most other things are approximately point sources, and even then it's unpredictable until you're at a sufficiently far field. And then there's free space, half-space (as with a wall mounted dryer), etc.
It is most similar to the effect of electrostatic charges. The effect of a point charge is the inverse square of distance, the effect of a line charge is the inverse of distance, and the effect of an infinite plane has no relation to distance.
It's more similar to an antenna that isn't an array. But you could compare an antenna array to a microphone array, sure. They both work by tweaking the phase and relative gain to arbitrarily change directivity without a need for physical directivity techniques. Like how home voice assistants and multi-antenna wifi APs achieve long distance reception without also amplifying 360 degrees of noise. They do a thing not unlike camera autofocus in that they quickly home in on whatever optimizes s/n.
Yeah, no joke. Kids shouting in your ear can cause permanent damage. I have a friend whose kid did that to them, and they now have problems hearing with that ear.
No worries, I know that's what you meant, and the point is that the power/intensity/volume/etc. at the source location really doesn't matter for this: at the listening position is what matters.
You're very likely some minimum distance from the speakers and from the dryer, but the minimum distance from your child could be nil (as in the 130dB claims) or significant (as in your experience), making it really hard to use something like a child in this conversation.
Mine did. My wife has permanent hearing loss from my daughter screaming in her ear. Years later she still says the best Mother’s Day present I ever gave her was a pair of gun mufflers.
I hate clickbait titles like this where there is no current age listed for comparison to the age referenced. Is the student 18 or 9.5? The time scale matters.
This reminds me of how Apple notoriously omits axis values during presentations just to make prettier-looking graphs.
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!!
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
>> 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
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.
> sometimes kids have reasons for what they say or do
Raising two kids I've come to think that this is almost always the case. The reasons may be based on misunderstandings but they are logically coherent in the context. A lot of times they may have a hard time explaining it, especially when an adult loses their temper because they decide the thing is just a folly.
In my kids' school they are not allowed to wear shoes indoors, but my son refused to take his off and wouldn't explain why to the teachers. It drove them mad, and we got phone-calls and emails telling us this had to stop that he must obey the same rules as the rest of the kids! We spoke to him (without reproach) and slowly we realize that he knows his shoes are expensive (because they are pronation) and it turns out that someone had hidden them before. After we explain to the teachers he is allowed to keep is shoes by his desk as long as they are not on his feet. Problem solved.
It makes you wonder about how teachers are selected and trained in the first place/what kind of behaviors are incentivized that they would not be able to handle a minor situation like this and had to resort to emailing/phoning parents when all that was needed was to just sit down and have a calm chat with the kid.
I imagine teachers don't have the time to have this type of 1:1 interaction with the 25 students in their class. Seems like email/phone communication to the parents is reasonable here. Something like disciplinary action would have been bad though.
I will add that it is 1 to 25 in California, other states vary.
One of the reasons why better ratios help kids is exactly to give this type of individual attention.
> and wouldn't explain why to the teachers.
Looks like they thought to ask him, but a kid's parent will be able to extract better info out of them.
Judging by teacher's earnings.. they are probably very badly selected and trained.
Interesting, thanks for sharing that link. I had a ton of weird tics as a kid which could easily be traced back to the large amounts of prescribed amphetamines I was forced to take under threat of punishment. The solution to the tics was... more punishment.
It took me years to realize things such as, the reason I would chew on my shirt color all day even though I would routinely get sent to the principal's office and publicly embarrased by teachers or beaten at home was just because my jaw would get very tense and chewing motions relaxed it, and my mouth was the Sarah Desert and sucking on the fabric pulled moisture into my mouth.
You too!? I thought I was the only one!
My shirts would be sopping wet in the front and would all have tooth holes from my chewing them, I'd go through a shirt a week nearly.
I wasn't on any meds but my teacher at the time would dole out punishments regularly to me in class. I've put 2 and 2 together before, but I never knew I wasn't alone in this behaviour! Thanks for commenting, this really helped me.
All those poor buttons. And then I come to find out that one popular tip for reducing dry mouth in dry environments is literally sucking on a button.
I wonder how common it really is in young children. Certainly seemed I was the only one dealing with it at several different schools. Is it too late to form a club?
Similarly, I had issues with scratching my nose in public, nail-biting, hair-pulling, picking at scabs, sucking my thumb at night... punished and beaten all the time for it, and some particularly nasty teachers would try to make a public example... come to find out in my adulthood that I have a literal disorder, body-focused repetitive behavior (BFRB) syndrome, which is related to OCD and bipolar disorder and ADHD which I also deal with, and heavily exacerbated and permanently worsened by my forced exposure to intense medication.
Did you outgrow the tics? If so, at what age and what led to outgrowing them?
I still deal with BFRB and I've had a few instances of old tics resurfacing, but a combination of practice and learning much about my disorders and cognitive science has helped me tremendously with everything else, such as nervous tapping, twitching, repetitive audible excitations, speech impediments and the like. I believe even my BFRB will eventually no longer be a problem. They all subsided at different points in my youth, mostly after conscious effort.
When I was first placed on medication at five, I developed a pretty awful tic wherein I would swallow every five seconds. I was sent to therapy and the therapist first thought I was lying to get attention and then thought I was crazy and needed more medication. This tic was causing gastrointestinal distress, dental issues from lack of saliva, and was a major speech impediment for me. My esophagus would get pretty raw. This was my first experience in learning how to deal with these on my own.
One tic that seemed to go away without extended cognitive effort (on account of its lower frequency) was extended periods where I would laugh uncontrollably over nothing for half an hour or longer until I was red in the face and choking for breath and my diaphragm was convulsing. This lasted for a few years until adolescence. My family thought I wanted attention again and would punish me when I couldn't stop at their command. It's honestly insane how some people respond to behavioral anomalies in their children.
Thanks for your response. My son is 9 and he goes through phases of having some sort of tic (throat clearing, head shaking, blinking, etc). They're not too bad, relatively speaking, and no one has really noticed. Or if they do then they probably dismiss it.
His pediatrician said it's likely a mild form of tic and tourette syndrome which often goes away by age 13. We haven't brought it up to him besides once or twice asking if he feels any discomfort. We haven't talked to him about stopping the tics and don't plan to. I hope his classmates continue to ignore it and that they remain mild.
Sorry your experience was not supportive and I hope BFRB does, in fact, go away for you.
I would say that habits are everything, and in some cases, I believe even extreme disorders like schizophrenia can sometimes be caused by bad neurocognitive habits degenerating unchecked.
You're doing the right thing by not making a big deal out of it or making them feel different, but as your son gets older and more able to have these kinds of conversations, it's worth opening a dialogue with them about finding ways to form new habits that break the old ones.
Many of my tics only went away after much effort, and growing up I felt like I had no one to talk to about them. My family didn't understand and I didn't have good experiences opening up to other children about them because they also either thought it was an attention thing or that something was really wrong with me.
At some point your son is going to become stressed by his seeming inability to control his own body and he will want to have positive dialogue about it. He may not have the courage to initiate the conversation though or he may be worried you won't understand. I wouldn't approach it with a bag of tricks but rather learn together with your son and encourage them to pursue better habits when apt. I know for me, accepting my disorders as purely physical and maintaining the belief that I could overcome them mentally was instrumental in my healing.
Good luck! I'm sure one way or another he'll figure it out as long as he is surrounded by positivity.
One thing to remember is that sometimes it's correct to realy trust your kids even in contradiction to your best assessment of the situation. The hand-licking story is about tactics for diagnosis, but another angle is that (sometimes) it's OK to not understand something, to think your kid is wrong, but to let them have their way anyway. Missing a plane vs dirty hands? Trust the kid, find another solution (grab a towel, wipe hands on pants, take the germ risk, etc), and talk about it later as best you can.
You don't want to let your kid be the boss of everything; you don't want to let your kid ignore your intructions or choose to do something fun instead of necessary work, but if your kid would rather stand there and do nothing while getting upset instead of doing some small work item, they aren't "cheating" you out of anything by getting their way.
Kids have a reason for everything they do. If you don't know the reason, it's because you've failed to communicate with them. Sometimes they don't know themselves, but that's still a kind of communication failure.
There are many things my kids were saying that I only figured out days, weeks or years later. Listen, guide them, let them be, and don't be a helicopter parent.
The Kennebunk rest area in Maine was designed by someone who hates children or is utterly incompentent or both. The diaper changing table is flanked on both sides by 4 loud hand dryers. The icing on the cake is the solitary paper towel dispenser is located ABOVE the diaper table. If you drew the short straw for diaper time, you'll be treated with your child screaming for mercy from the dryer noise AND have people who prefer paper towels dripping their wet hands all over your kid.
I'm with the child on those tap dryers. They seem designed to blast any remaining drops of water in the bowl into your face or shirt. Hate the damn things and avoid them now. Maybe the places were using the wrong bowl or something. :)
I saw these for the first time on monday. The first thing they did was blast all the water in the sink into a fine mist and spray it over me. I can't believe that the people who designed or specified these ever used them.
Thank you for sharing that link. Truly.
In re: "the hand licking incident"
Oh the pathos! If only they had known of the "Six Step Reframe" algorithm (which is actually deprecated now in favor of even more effective algorithms.)
In pseudocode: https://gist.github.com/calroc/4719702
The hand-licking incident is more like /r/kidsarefuckingstupid.
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.
Children do not see more colors than adults.
The cone cell of the human eye is the main type of photoreceptor that senses differences in light bandwidth, aka color. The dics of the cone cell are tuned to be receptive to certain bandwidths of light. These bandwidths are well understood and do not change as humans age (outside of damage to them)[0]. Humans only have 3 sets of these cones and do not gain or loose new types of cones as we age. The receptive bandwidths of the pigments are set by the biophysics of the molecules.
The perception of color does change as humans age, however. Typically, a newborn cannot yet use their eyes well. They can percieve light and dark, then red, then they can process depth, etc. This learning process takes a few weeks to months[1].
The cognition of color is a very in depth and facinating field. Thus far, it appears that color is a cultural and learned thing, in that if your language does not have a word for a color, it seems to be very difficult to determine the color as a different one from among other colors. Translating the mix of photons that your photreceptors are affected by into usable language is a very complicated process and is not well understood yet.
Fun Fact: The Illiad does not include the word blue and the Bible uses it very rarely as well.
[0] https://en.wikipedia.org/wiki/Cone_cell
[1] http://www.bausch.com/vision-and-age/infant-eyes/eye-develop...
A great podcast on color from radio lab if you haven’t already heard it: https://www.wnycstudios.org/story/211119-colors
In short they specifically go into how we perceive color etc. great show!
Also, we hear using the cochlea, a spiral sense organ that sorts sound by frequency. In children the whole thing is much smaller. So they hear much-smaller wavelengths of sound which means higher-pitched sound. As we grow so does the cochlea so we hear lower and lower sounds and lose the sensitivity to the highest-pitched ones?
I'm guessing that hair dryers have a scream in the upper register that adults don't normally hear.
That's very possible indeed. I remember when I was a kid my grandparent's tube TV was making a high-pitched sound that was figuratively driving me insane (maybe generated from the HSYNC frequency, now that I think about it). I couldn't understand how they could bear it but of course when I told them they didn't get it because it was probably way outside of their hearing range. I'm fairly sure that now that I'm in my 30s I couldn't hear it either.
https://en.wikipedia.org/wiki/The_Mosquito
> The Mosquito or Mosquito alarm is a hand wound machine used to deter loitering by young people by emitting sound at high frequency, in some versions so it can be heard mostly by younger people.
> The sound was made into a mobile phone ringtone, which could not be heard by teachers if the phone rang during a class.
At 35, I'm still deeply bothered by that sound. Slightly related but in a lot of parts of Ginza in Tokyo, they use a similar sound for repelling rats that I find extremely uncomfortable...
Typically a high-pitched whine from a CRT is from the flyback transformer. I found, when I was a kid, that sometimes a well-placed whack on the CRT's cabinet could temporarily fix the problem.
Nowadays, I have no idea if I can hear that whine anymore or not, as CRTs are quite uncommon. Probably not. Much for the better, as it used to give me headaches.
15Khz colorburst whine. Its amusing how many audio recordings even today show a notch filter used at that frequency, years after there were no CRTs anywhere in the recording process.
There are recordings that really should have had it!
https://open.spotify.com/track/3B4q6KbHbGV51HO3GznBFF?si=Fgy...
https://open.spotify.com/track/6PsISpFaCEKwysPfwO9SfC?si=NQa...
(Or if these whines aren't CRT related, I'd be curious to learn the source).
Flyback, not colorburst. Monochrome sets should exhibit the whine as well.
I was quite surprised as a young adult when one of my ears couldn't hear cricket chirps anymore. If I laid with one ear against the pillow I could hear them, but if I turned over it was silent. A hearing test confirmed that one ear was deficient.
You might still be able to hear it.
https://youtu.be/8XzNh5U8Jzw
https://youtu.be/rkEQ0b35nzw
I have read this many times online and i think i must be the only one who for some reason liked that CRT sound :-P
Though it might be that since i really loved computers, i associated it with computers and liked it via association.
I'm 39 and I can still hear 15kHz flyback. Not as loudly as I used to be able to, but it's still there.
This is not true.
The dimensions of the cochlea are basically fixed at the time of birth. As the dimensions of the cochlea are the main contributing factor in what tones are able to be heard, the tonal bandwidths are then set at birth as well (minus hearing loss due to damage as we age). If you are interested in how sound is interperted by the brain, be aware that it is not a straightforward process and takes a bit of research. Still, the cochlea is essentially fixed at the time of birth.
More on how the dimensions of the cochlea determine tonal bandwidths: https://en.wikipedia.org/wiki/Hair_cell
[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3970226/
[1] http://www.ajnr.org/content/ajnr/early/2011/09/29/ajnr.A2713...
It's not due to cochlear size, we lose sensitivity to high frequencies because the hair cells slowly degenerate with age.
It's not only due to size...
Does that mean that children also don’t hear deep bass? Is it commonly accepted that young children don’t enjoy the sort of music (e.g. dubstep, drum-and-bass) that employs near-infrasonic notes?
An other thing to consider with deep bass is that, at least in concert/club conditions, you feel the bass with your body on top of hearing it. So even if your ear struggles to capture those low frequencies you'll still experience them somewhat.
Even as adults, you feel anything below 45hz or so more than you hear it. I am confident that children feel too. But the bass heavy club music ypu describe has an adult cultural element, otherwise missing from most music.
"Children see more colours as well."
I'd be interested in hearing more about this. I understand the mechanism whereby audio sensitivity is progressively lost but I don't see why getting older would result in seeing fewer colors. Is this perhaps instead that we are less sensitive to color, requiring more photons to have the same color experience, but not actually seeing "fewer colors" in the sense that there are colors that fall off our gamut entirely? That would make sense to me.
discrimation (horizontal) vs sensitivity (vertical)
As we age, we lose some hearing power and visual acuity, for physical reasons on the organs.
As our brains mature, they learn to not discrimate among certain "unimportant" sounds and colors. Adults can't lose the ability to disambiguate among novel language phonemes from foreign languages (as perfectly as kids can), and similarly they lose ability to distinguish similar colors that they learned are irrelevant. This isa tradeoff adaptation, so you can see a shadow gradient as single color instead of a complex spectrum, understand that traffic lights are showing the same signal despite variation in frequency, etc.
On another level, very small children (babies) have poor color vision, because their eyes and brains are still missing basic development.
So it's a curve: newborns have poor hearing and vision tha rapidly improves for a few years and then decays slowly, for both physical breakdown and for mental "optimization"
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.
Agreed. Luckily there is a small delay between pushing the button and it actually flushing. I usually press the button and then cover my ears until it stops again.
Except the button is probably covered in other peoples' pee so I wouldn't touch my ears without washing hands.
Hold a piece of toilet paper to flush, then drop it when bringing hands to ears.
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.
Our local fast food restaurant has one of those. Coincidentally it's also a Dyson brand. They don't work very well. Water and crap gets everywhere!
The Dyson combined tap-dryers are awful, awful products - we have some in newly fitted bathrooms at my workplace. I don't know how they made it out into the world without shame. They're hard to trigger reliably, they blow water everywhere, they're generally cumbersome and unpleasant to use.
That's amazing. In a 2 minute promo video with many clips of people washing hands, and many clips of people drying hands, they never show someone washing AND drying hands in the same clip. They know the poducts doesn't work at its primary value-proposition.
https://www.youtube.com/watch?v=PkpP-mEUcAs
I’ve seen articles about Dysons filling the air with dispersed virus.
I swear by their vacuum cleaners, but none of the Dyson hand dryers are good. The boxy air blade ones are the worst I've used so far, but I haven't seen the tap ones yet.
Even the vacuum cleaners are meh at best. Beautiful from the outside, excellent finish but disappointing performance and features for the price.
We have one and it is like trying to drag a tank around the house into small spaces. Like all Dyson products, it's cleverly engineered and presumably hasn't once been tested with an actual customer.
Their stick vacuums are light, although the battery life is short. They are quite effective but only if you use the right head for the job. There is one head for carpet that is amazing for carpet, but it's terrible for hard floors. There is a head that is great for hard floor, but obviously terrible for carpet.
I love the stick vacuum for cleaning stairs, it's far more convenient than dragging a full size one up/down the stairs. Agreed that the battery life is too short.
Not really beautiful - they're 100 percent plastic and look like a child's toy.
At least put some anodised aluminium somewhere on it to make it look 21st century!
I’ve seen them use fancy metallized plastics in place of anodised aluminium.
But yeah, I guess most Dyson items do look pretty awful.
My secret trick for the air blade dryers is to move both hands in opposite directions so it never turns off.
I was in Japan recently and they didn't have the Dyson one but they had very similar models from Panasonic and Mitsubishi and they were much quieter and somehow worked better. We need those.
Can confirm this - the hand driers I've seen in japan were generally pretty small, yet very effective and quiet.
>Water and crap gets everywhere!
I've only seen those taps with trough sinks[1], which limits the mess.
[1] https://i.ytimg.com/vi/nZfqFvsuE3s/maxresdefault.jpg
You are supposed to use water and soap to wash off the crap first.
I haven't seen one of those Dyson pieces of shit without at least some gunk or water sitting near the bottom, not draining or sliding into the airflow. Even if you get everything off your hands, having a stupid plastic device with a deep crevice in an environment with fecal coliform presumably floating around is a _great_ design let me tell you.
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 always think they should just take it down and put up a sign that says, "Too cheap for towels." It won't damage my hearing and will get my hands just as dry.
Let’s not even mention how they always try to justify these monstrosities by saying they’re better for the environment. Insult to injury.
YES!
"This device saves trees"
No, it doesn't. We should be (and AFAIK often are) at the point that paper towel pulp is coming from forests we replant. Also, I don't know, maybe those dryers "save trees" but the paper towels provide a forcing function for someone to always have a couple of ready forests on hand, which seems better?
Yeah, I just don’t buy it. 100% recycled paper towels are a thing. And if you really want to get technical it seems like manufacturing and using those devices consume far more energy. Anyway, glad I’m not the only one shaking my head at these things...
Honest question: Have you tried just vigorously shaking your hands and then letting them air dry? It only takes a couple minutes. Worth the wait to still have clean hands.
Honest question: is there anything about my comment or profile that suggests I’m open to receiving hygiene suggestions from a complete stranger on the internet? It’s not like I don’t know how to have clean hands, just saying.
>is there anything about my comment or profile that suggests I’m open to receiving hygiene suggestions from a complete stranger on the internet?
It's probably that you're participating online in a discussion about hand-dryers, and, by proxy, washing your hands -- and expressing your disinterest in using them (hand dryers) .
It might even be the fact that you've said that you considered not washing your hands all together when posed with no alternative -- a danger to others besides yourself.
I find your tone to be entirely unwarranted and rude.
'Just saying.'
Actually, it was the part where you stated you considered not washing your hands? And I was honestly asking because most people don't realize how quickly human skin dries. I hate air driers also, but I generally don't use paper towels anymore either unless I'm planning on needing dry hands within a minute of leaving the restroom.
Or, hey, we could go with your interpretation that I'm a raging asshole that thinks you don't know how to wash your hands. Whatever floats your boat.
Sorry. I assumed I was being trolled and reacted accordingly.
I was being ever so slightly hyperbolic in my statement about not washing hands. For the record, I do use the time-honored air-dry, shake-hands-vigorously and/or dry-on-pants methods when circumstances demand.
>my kids just plain refuse to wash their hands out of fear of accidentally triggering the dryer
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...
same with lawn movers, the sounds and vibrations hurt kids. I couldn't stand using one until about 15 or 16.
My kids had a pathological fear of the automatic flush toilets when they were little. They were so loud, and they considered them out of control.
Who would have thought Hand Dryer buyers would have such a nice ecommerce website to shop on!
I wish every ecommerce store looked as good and simple as that one.
I had a similar problem as a child with hair clippers at the barber... some were really loud and were put right next to your ears!
if its bad for kids, imagine dogs.
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.
that sounds like a sensory processing issue.
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?
I got started taking a basic hand tools class and followed that with other evening and week-long classes. I'm actually not somebody who's been in the shop since they could walk; I'm pretty late to the trade.
At the moment it's like that old joke: "What do you call a drummer without a girlfriend? ... Homeless." I do make some money on commission work, but not enough to cover my living expenses. What I do make I'm largely investing back into the business, which I just started. This is probably fewer tools than you might think; I pay for annual access to the bigger tools I don't have, and I have a pretty decent selection of the moderate-sized tools that I got for pretty short money (band saw, drill press, and table saw. All good tools, total: <500 USD).
Mostly it's stuff like a camera and lights to shoot my work, a logo, and the other sorts of things that separate a hobby from a business. A better website [0] is on the list as well, but never having been a web developer, my partner and I are likely going to use squarespace or something similar.
Am I glad I made the switch? Emphatically yes. I love the woodworking aspect. I'm happy to report that my partner is helping with the business-y things. Also: she's a way better photographer than I am. Any of the pictures on my existing website that look good are probably hers; the crappy ones are mine (and need to be re-shot around the time we get around to settling on a logo and commit to getting a real website up).
TL;DR:
I'm lucky to be married to the world's most supportive partner.
[0] http://longwalkwoodworking.com <- HTML like it's 1998, CSS lifted pretty much straight from the "68 bytes of CSS..." article posted here a while ago. There really do need to be pictures on the home page, a contact page, an about page, etc. Hosted on github pages, no Jekyll, etc. I threw something up so that I could put a URL on business cards and have it go to something.
Holy crap. This may seem weird, but I've been looking for boxes. I've got way too many small things that don't seem right in the open, but also don't have purpose built containers...
If you're interested in making a few I'd love to buy a few veneered boxes ( in the pictures presumably taken by your wife ;P )
...For real, I have a primal need for boxes that don't feel threatened by a stiff wind or a few ink wells stacked inside...
email is in my profile if you're interested :)
Really great looking stuff. How long did it take to get your dovetails perfected?
Thanks! I'm still working on getting the dovetails perfected. Like a lot of things, they require practice. While I usually get them right, if I haven't cut any in a while, they often come out a little rough until I get my hands used to making the right motions again.
Really perfecting them would mean getting them both accurate and fast. I definitely need to cut a few more to get to that stage, and do it regularly to keep it there.
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.
My parents used to use the vacuum cleaner to put me to sleep as a kid, even into my toddler years.
One night they forgot to turn it off and the motor burnt out.
To this day, I sleep (and often concentrate) better with some white noise going - turning on the bedroom fan is an essential part of my night-time ritual. There's some evidence that loving white noise is linked to ADHD, but I don't think that it's predictive for a 4 month old. :P
Newborns like loud environments. A birth changes environment for child from very loud to a very quiet. I suppose it feels like sensory deprivation for a child. Seems that hand dryer reminds your daughter a good old times before her birth.
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:
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.
For what it's worth, I've seen (and used) those in gyms and bike lockers at offices as a hair dryer. It's possible the person/company who bought it and installed it did not know what they were buying.
I don't know that there's really any difference between this and a hand dryer, but I've certainly used them as hair dryers too.
According to the company that makes them, that is indeed usable for drying hair:
http://www.xlerator-hand-dryer.com/ExcelHairDryer/RH76-C.htm...
Given that they also have an almost identical product that is a hand dryer, you can inspect the pages to find the key difference:
http://www.xlerator-hand-dryer.com/ExcelHandDryer/R76-C.html
"For hand dryers, timers are set at 30 seconds and at 3 minutes for hair drying."
It's probably that the nozzle can be rotated and point upwards at your hair.
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.
> men’s stubble
One of my great joys in life is how much my daughter loves my stubble. She grabs my face with both her hands and declares “Sooooo scratchy!” and then squeals and laughs when I nuzzle her cheek with mine and pretend to be a horse. From ~3 yrs old, now going on 10.
My heart will definitely break a notch if the day ever comes she outgrows that!
She may outgrow it, but she'll probably never forget it.
I'm a guy, but I recall as a kid feeling my dad's stubble when I gave him a hug as a child, when he came home from work, smelling of sweat and tar (he worked as a road maintenance worker - a very hard job, especially in the summertime in California).
He passed away 14 years ago, and I'm turning 46 in a couple days; how time passes...
Same here. My strongest sense memories of my dad are the feel of his shirt against my cheek when I'd run up to hug him when he got home from work, the feel of the callouses on his fingers, and the stubble on his cheek under my hand.
I remember those things more often than I do the sight of his face, or the sound of his voice, or the smell of his cologne. By far.
Can confirm—and ah that sounds familiar. My own dad was a pipefitter-wleder in an oil refinery.
I can still smell that and the feel of the work denim he'd come home in.
reminds me of this particular comic http://www.smbc-comics.com/?id=3317
I love that my kids love it too. I hate that it immediately makes their skin break out as if there's a rash, though. (All fair-skinned red heads).
> cool water makes small children shiver
Is it just my kids then that seem absolutely immune to cold water and will happily jump into unheated swimming pools, and will happily have a cold bath?
I noticed my boy was happy getting into cold water as a toddler (compared to adults who suffer during the transition from air to cold water).
Now he's four years old, and a few weeks ago we swam together in a cold lake. He was happy to get in, but after ten minutes I noticed that his teeth were chattering and his lips were blue, while I was quite comfortable.
Having been a cub scout leader and now a parent you see that kids don't really have a great sensitivity to their own body temperature. They'll wear hot coats in Summer and tshirt in Winter unless you tell them not to, they're usually pretty far gone (sunstroke/hypothermic) before they will realise for themselves that there's something wrong.
I don't think they really get a good idea until they are about a year in to puberty, and even then they're more prone to mismanage their clothing (but I think that's just experience).
Also worth bearing in mind that younger kids have higher body temperature, and that they usually have lower surface area:volume ratios than bigger people.
There are two dimensions here -- one is that they may not feel it at all; the other is that they may feel it but not realize it's bad until it's too late, and might not attribute cause.
For example, going out in the cold doesn't hurt at first, but the pain builds up. As an adult, you may react to the initial no-pain sensation because you correctly predict you'll be freezing later.
Also consider that as an adult the same feeling can be both good or bad by mental context: consider a warm toilet seat -- warmed by a fancy Toto heater at home vs warmed by a stranger's buttocks in a fast food bathroom.
I have a hunch its the same ‘physiology’ that causes selective hearing. “Please turn off the iPad!” vs “who wants ice cream?”
I was like that as a child. As an adult, I’m always hot, unable to live without air conditioning, always looking forward to cooling down with a swim or a cold shower. (And I live in Canada; it’s not like the ambient temperature is all that high!)
Maybe I was that way as a child as well, and just wasn’t introspective enough to notice.
As an adult, I do get cold eventually, though; I can’t stay in cold water for hours, like I could as a child.
I think in this case it has more to do with that kids (and younger people in general) can hear better and at a broader frequency spectrum. I (and I know other people with the same problem) for example am always irritated why induction cooking plates make such painful noise but as most people cannot hear them, industry gets away with that. Same for those ultrasound devices to protect cars against martens that can get as loud as 200 Db.
I assume you don't really mean that affection is painful for small children...(?)
I guess they're referring to things like kids running away from distant relatives who want to kiss and hug them, which is definitely something that happens.
Probably because of the big sloppy kisses that grandmas tend to distribute.
That's definitely part of it, but I think (and I also remember) that a part of it is that children have a well-developed sense of personal space and who they are close enough to for different types of contact, from a pretty young age, but their sense of closeness is (quite reasonably) derived from actual (remembered) contact rather than from having a genetic relationship or contact before they can remember.
It's not so much a conscious sense of personal space as it is discomfort with the unfamiliar.
We have to remember that kids don't have any reason to love distant relatives, and that adults don't have the right to demand physical affection from kids.
Cheek tweaking, heavy pats on back etc.
I remember my dad would rub his stubble against my cheeks when playing monster after he caught me. It was always so intense and visceral. I loved it.
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?)
> at least half of those vehicles are louder because the driver desires it
Motor cycles are the worst for this. It's not rare to have whole neighborhoods woken up because one of those passes through.
I recently learned that (at least in the US) those loud motorcycles are actually illegal, and that it is near-standard practise that motorcycles are sold with cheap but compliant mufflers which everyone knows (wink wink) will be replaced with aftermarket loud (but illegal for road) mufflers.
I applaud the research of this young student, showing that noise pollution is not just a nuisance, but a real health concern. Young ears getting permanently damaged is one aspect. Entire neighborhoods losing nights of sleep is another.
Relevant article where police mention that they simply are not given a proper decibel meter: https://patch.com/california/berkeley/ask-a-cop-why-deafenin...
When a loud motorcycle [0] goes though a city at night, I wonder how many people it wakes up. It could easily pass thousands of people with just a few miles of driving. If 1% are woken up, it could still cost dozens of total hours of sleep.
Based on how much a loss of sleep lowers performance (and increases health risks), the total cost of that one motorcycle driving one night might be huge. The cost of the health damage and lost productivity might be about as much as stealing a car.
Since the cost is spread out over a lot of people, we don't tend to care as much about it.
[0] Likely with the muffler deleted. While technically illegal, no one enforces any laws related to the noise output.
Not sure why you're getting downvoted here. In Brooklyn and Queens, this happens a ton. If a loud motorcycle happens to rev when you're on the street, it's viscerally terrifying.
There is a reason for this. When car drivers stop pulling out in front of motorcyclists, motorcyclists will stop fitting loud exhausts.
Sure, that's why open pipes at three AM are run full throttle in second gear on a city street with thousands of houses. It's simply narcissism.
I had the pleasure of living on Overtoom in Amsterdam, which is a beautiful street but I'm a relatively light sleeper and even at the back part of the house you'd be woken up several times every night by some 'look at me' dude making as much noise as possible. Not a car pulling out in sight at that hour.
This is the same tired excuse my friend made when he got a loud bike.
It’s just not true. He later told me he enjoys the feeling (vibrations) and that there was something primal about “taming” something that sounds powerful.
As for car drivers, you should be assuming they can’t see you. Driving defensively is the only way to stay alive and you can argue that it shouldn’t be that way but it doesn’t make it any less true.
Modern cars are so sound-insulated that the volume of the motorcycle isn't going to have that much of an impact in normal operation. Fit a louder horn to the bike if you need to draw attention in specific situations.
Loud exhausts are definitely not designed to make motorcycles more noticeable to cars.
I ride and do "feel" the sentiment that loud pipes might help in some situations. But here's a rider-centric article that helps address the situation _and_ provide some actionable advice.
https://www.revzilla.com/common-tread/stop-saying-loud-pipes...
Thanks, that article makes lots of good sense. I see more and more riders (on relatively quiet bikes) drive with high visibility gear, especially on the highway, which is great.
But those are rarely the 'loud' types, they're just people using their bikes as transport rather than as an attention seeking device.
> in the emissions process most states in the USA perform
I'm not sure how accurate that is. From what I can tell, only about half of states have some region that requires emissions testing for some vehicles.
https://en.wikipedia.org/wiki/Vehicle_inspection_in_the_Unit...
For example, Washington requires testing in part of 5 counties (out of 39), for non-hybrid, 4-wheeled vehicles older than 2009. But even that is misleading, as the emissions testing program is being discontinued entirely at the end of the year.
So even if they wanted to just add noise testing (it sounds so simple!), most cars don't get annual testing, and in another 6 months, none will. The state won't even have facilities for it.
The bigger issue I see is that emissions is generally seen as bad by everyone. Most people don't spend money to mod their car to pollute more, so if you test cars once a year, it's probably going to be OK the rest of the year. People do mod their cars to make more noise, though, so if you test once a year, they're going to fix the noise for the test, and then put it back the next day.
To fix this problem, you need to be able to catch people on the road.
I didn't realize how tragically limited emissions testing is (everywhere I've lived in the last 37 years has required it.) After some cogitating, I think you're right about enforcement needing to be done on the road which is unlikely to ever happen.
How hard would it be to make a drone that hones in on the loudest car nearby and snaps a picture of the license plate?
I was thinking something a bit more simple like a smartphone with a directional mic and opencv could work - at least for getting an idea of the scope of the problem. Put one on each side of a two lane road and you could probably get accurate results.
It's not 50% unless you live in a tight-knit ricer neighborhood. It's not a trivial option to customize a car to make it louder; it takes a bit of effort.
What is true that we tend to notice annoyances more than non-annoyances, and that the car may be louder because the driver want to accelerate or velocitate more than they should, and noise is a side effect. Or the stereo is louder than it should be, not because they want you to hear it, but because they want to hear it and they don't care about you.
My observations are a bit different. I live in a populous suburb (150k residents?) north of Denver. Truck culture is very prominent here and mainly consists of raising a vehicle and making it louder - mostly because they do want to attract attention. My 17 year old neighbor modified his Subaru so that it can (literally) be heard from miles away - and when he simply turns the car on can be heard clear across the entire neighborhood until the engine warms up and throttles down.
I'm not so much annoyed as I'm curious as to how all of this noise affects the environment at large (people's sleep quality and mood, birds migrating, insects mating etc.)
https://www.abc.net.au/news/2009-02-04/phantom-expander-targ...
It can actually be extremely trivial and cheap by just drilling holes in your muffler (yes, I've seen this). Or by installing a glasspack for ~$20. This is what everyone gets annoyed at, usually.
I'm surprised that making sure noise output is sane isn't a standard part of certifying stuff for human consumption, but then I guess that's the whole "free market will sort it out" idea not working as expected. Nice to have work like this to say that maybe it would be a good idea :)
It isn't just the "loud" noise, either. There's a giant white and dark grey yacht parked in the Vancouver Harbour about half of the year. (It's the one near Jimmy Patison's yacht, except at least twice as large and probably modelled after a Star Destroyer). I have never seen it move, but as long as it is there, it emits a low-frequency hum that causes noticeable churn in the water over a ~150 meter radius. It is like a giant, evil subwoofer of the unreasonably rich. It's frustrating to paddle anywhere near it, it gives me a headache, and I can't imagine what it does to animals that share the water. Whenever I'm near it I'm bothered that the thing is allowed to exist, let alone park there.
> Would it be so difficult for noise pollution to be regulated like emissions
Are there no noise regulations for vehicles in the US then? EU does have these thankfully, currently 74dB but meant to go down to 68dB by 2024.
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.
I refuse to use the Dyson at work for precisely this reason, and I try to not be there when other people do - our bathroom is a rather small confined and reflective place.
I find that Dyson makes some of the quieter hand dryers I've encountered, although maybe that's because they tend to be in larger restrooms. Starbucks really hurts my ears with much older style hand dryers in their single-occupancy restroom.
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.
https://www.health.harvard.edu/blog/the-bacterial-horror-of-...
Most environmental health regulations (all the ones that I know of, at least) forbid the use of air hand dryers in restaurants and public kitchens, instead requiring paper towels. That should tell us something.
Yes. That no hand dryers work correctly and they need to stop being installed.
They are terrible. Saving paper towels at the cost of spreading bacteria and giving everyone moist hands is not a good trade off.
The high school near us has no paper towels or air dryers. Kids use their pants.
Children, being shorter and in front of the air blast may be more likely to have whatever crap is on their wet hands blown back into their faces.
Dyson models do have HEPA filters on the air intakes.
That doesn't help when the air outlets and inside of the drier fill up with gross slime mold
Just don't touch the basin area in the bottom!
Just don't touch is a tall order with Dyson hand dryers. They are fundamentally hard to use correctly because of tight clearances.
The way they work is based on the idea of a narrow stream of air that gets water off your hands better. But for the stream to remain narrow and not dissipate, you have to get your hands close to the equipment. It's based on almost but not quite touching it.
Positioning your hands in a careful and controlled manner is, ergonomically speaking, an uphill battle. So on average, it won't happen often.
In other words, Dyson hand dryers kind of trap you into accidentally touching the part you don't want to touch.
Worse, the same applies to all the people who used the hand dryer before you. It's a very reasonable bet that the surface where the air comes out has been touched by someone who didn't use soap when they washed their hands.
I can't say I've ever experienced this issue with the air blades. They seem easy to use them without touching any part of the hand dryer. I'm surprised that people have trouble with this!
Are you some kind of superhuman? Even if you try really hard and aim precisely, as soon as the air turns on your hands get pushed to one side because the pressure is not exactly the same in both sides.
Weird... maybe they are different where you are? Older models, or not installed/adjusted correctly?
I use these all the time (they’re pretty much everywhere in the U.K.) and haven’t experienced this unbalanced pressure issue. They always seem pretty much equal pressure on each side to me.
Their official usage video shows touching of the sides and that person doesn't appear to have particularly large hands either.
https://www.youtube.com/watch?v=ExuvJkZ61Cg
With large hands, there's an extra degree of difficulty to avoid touching the sides and the bottom. It still leaves you with wet wrists and damp fingers.
Plus, the stream of air pushes your hand into the surface you're trying to avoid.
An interesting study, but I wouldn't read too much into it. Who's to say that paper towels don't collect and deposit just as much bacteria onto your hands?
They're single use and kept in a dry place.
They are not sealed from the ambient air (not usually), which is what this study is saying is where the bacteria comes from.
Regardless of what common sense might say, the point is that the study didn't actually do a direct comparison.
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.
But what are the alternatives?
- 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.
Paper towels are recyclable and made out of recycled paper, at least. They are the most hygienic solution out there.
I still see the towel rolls around, they're a good option as well. Maintenance for (esp. public) toilets is never not going to be a thing, but it does require a bit more infrastructure to maintain (= washing out etc). But there's companies that will take care of that.
Not offering hand drying is the worst; drying your hands is arguably even more important than washing them when it comes to hygiene.
Anyway beyond that, fixing the hand dryers is also an option. Use larger but slower rotating fans. Dyson's machines have the problem that they have relatively small, high-speed motors.
They're not recyclable. If they're made from recycled paper, their fibres will be too short, like tissue paper or toilet roll.
On top of that, people might be using it to wipe anything, which could potentially ruin the rest of the recycling.
If you're putting any of that into your recycling, you're doing it wrong.
Also, do not recycle any paper/cardboard with grease or food contamination, especially pizza boxes with grease on, they will also ruin a recycling run.
> If you're putting any of that into your recycling, you're doing it wrong.
Hence the main problem with recycling. No reasonable person can know all the rules about plastics, what kinds of papers, etc. Why can't sorters sort it all out? Because nobody knows what to pre-sort.
Oh, come on. If you're capable of navigating normal life, you're capable of recycling. What you're saying is that you won't spend five minutes absorbing a one page document.
Recology has probably the most complicated arrangement I've had, and, well, this is not exactly rocket surgery:
https://www.recology.com/recology-san-francisco/what-goes-wh...
Nice. What puzzles me is fast-food places with 3 bins (compost, recycling, trash) with these pictures on each -- when instead the pictures should be of the actual containers/wrappers that the restaurant uses. Wouldn't that be more helpful?
"that" in this case is the sort of things one finds in a bathroom. I don't think a reasonable person would think they ought to sort human waste with recyclable paper.
IME paper towels always go into the regular trash. Is this unsustainable? I thought paper was pretty environmentally sound.
For paper producers who replant the trees they log, they're actually sinking carbon so that's good. If they don't replace the trees, no bueno.
They are compostable, not recyclable.
I wish the rolling towel devices were more prevalent. I think I've only encountered them once.
We used to have those everywhere in Vancouver. Unfortunately they got rid of them because teenagers were daring each other to strangle themselves unconscious using those things, and several people were badly injured or died.
Humans...
I feel your pain too well. So many good things we could have in society, but due to a small minority of people ruining it for the rest of us.
Another poster mentioned that their child's high school didn't have any paper towels, which I can only assume is because the kids were wetting them and throwing them around the bathroom ceiling and walls to make them stick, which is something even I (regrettably) took part of as a middle school child.
Maybe I'm filthy, but I've always just patted the back of my shirt unless I'm in a place with clean cloth towels available.
It's not the outside temperature that'd discourage the already apparently slim number of people that do bother to wash their hands. It's water temperature. And if the water is freezing, no drying method will get the average joe to endure the pain of water hitting their hands.
I'm a proponent of cloth rolls. Toilets need regular maintenance anyway. Perhaps an air blower would function as a backup, but I'd honestly prefer drying my hands on my clothes, since in my experience air dryers are either ineffective or in the case of air blade systems so nasty that I don't want to go anywhere near one.
"Paper towels?"
yes, paper towels, perfectly recyclable and hygienic. Allows wiping face/neck as well.
I don't get the discouraging part and cold climates. It requires hot water, but that's it.
Even with hot water, evaporation rapidly cools the water and your hands get cold.
Yeah, it always annoys me when it's impossible to splash water on my face and dry it (perhaps I am a uniquely sweaty mess, I dunno). With most dryers you have to make some sort of cup shape to rebound the air into your face, and that's if you aren't instantly thinking of all the germs blasting out.
See above, learn how to recycle properly, you shouldn't be recycling paper towels.
Appreciate it. So the towels are good for compost and they can't be recycled any longer.
While I was at uni just few years ago all bathrooms had the towel on the roller. The main issue was that by the end of the day the entire roll has been used so you either re-used the same final patch of the towel that everyone already used, or don't dry your hands. Otherwise, great idea.
> - Washable towel on a continuous roller/spindle thing? Common in past decades, now pretty rare. Requires regular servicing. Expensive? [1]
Not true by my experience. I'd say maybe a third of the toilets I use (in Europe) have these cloth rolls.
Paper towels? Environmentally unsound.
I don't see why these paper towels would not be 100% recyclable or that much different to regular toilet paper. Also, what if people would like to wash other body parts that can't be put in an airblade e.g. face?
I'm not sure why you're being downvoted, I mean I know why people are but I don't think they should be.
You're forgetting that we have to create paper towels/toilet paper, etc. from trees. And we aren't just talking a few trees, it's a deforestation issue.
Sure we could replant trees, etc, etc, but it still destroys the current eco-systems living there.
As long as they come from farmed trees and wind up composted, they're actually sinking carbon out of the air. Maybe it's not a net win because of the energy used to create them and move them around, but towel itself will lock its carbon in the soil for quite some time.
Live in the cold climate of Canada. I dry my hands by slapping my pants when I walk away from the sink. Then again, I also eschewed towels for the longest time in favor of slapping myself dry after showers
> 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.
The "zero maintenance" is part of the problem. Any hand dryer should have an air filter, and that air filter should need to be replaced frequently considering the nasty things that happen in that room.
> 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.
They are cheap. That’s why they exist. Bathroom operators give zero shits about the environment.
With paper towels, you need to visit a busy bathroom a few times a day to empty the trash.
I rather use my own t-shirt to dry my hands than use a hand dryer. It should have been years since I last used one. I hate it since a child.
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.
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'm most concerned with touching the handle/door with a bare hand. Too many people don't properly (or worse, at all) wash their hands after using a restroom. Therefore, I stick with the paper-towel grab.
The step-handle is a nice solution to this, sometimes.
I almost always wait for someone to open the door if there's no way to do so without touching nasty door handles. Or find a tiny piece of paper to use and discard afterward. Or hold the door with my feet while I clean my hand after opening the door with it, if possible. When I go to restaurants sometimes I carry a paper napkin if I have been to the place and know it's complicated to get out without touching anything. Yeah, I'm that paranoid with it...
* Heck, I even change clothes when I get home before seating in my bed or sofa.
Seems legit
People won't touch the restroom door handle, but they'll touch every other surface in the facility without a second thought. Walking through a bathroom door doesn't magically make hands clean. The good news is if you have a healthy immune system you can touch anything, including the bathroom door handle and you'll be fine.
I've never understood why more restroom doors don't open out. It's empirically better if you can just push the door open with an elbow.
It should be an international standard that: * rest rooms have never-empty paper towels * rest room doors have a trash can next to them
or simply restrooms with no doors like most airports
If there's no lock/handle, I 'kick' the door just to avoid touching it.
If I'm wearing long sleeves, use my shirt sleeve; if I'm wearing short sleeves, grab the bottom of my shirt and use as a glove. I've seen too many people drop mega-bombs in the stall, sound like they're making a hash of the cleanup, then explode out of the stall and walk right past the sinks. Why would I wash up just to get feces on my hands from the door handle?
Please use the paper towel grab. Don't disrespect your shirt like that, which will still be on you wherever you go the rest of the day until you change it.
> If I'm healthy, it is also good for the environment.
"Patient Zero" doesn't usually exude symptoms until it's too late.
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!
Not to mention studies showing that hand dryers, with the Dyson models leading the pack, do an excellent job of distributing bacteria over a large area.
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
I’ll rather walk out with dripping hands
I feel the same. I dry my hands on my trousers and wear headphones in the toilets to avoid the blast of white (?) noise from other users of the high-speed dryers at work.
It wouldn't surprise me if the UK regulations on these devices also only measure the noise levels without hands in the airflow... there's no way these are legal when they are actually in use.
Don't know why you are being downvoted, but at my gym I go through the same situation. Whenever I go into the change room/washroom, I go to the locker furthest from the dryer, meters away from it. It doesn't really matter since every time someone activates it, it sounds as if it blowing right next to me.
Why not dry it with tissue paper?
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.
The motion activated ones go off when you move a little, not when you stand up. I've had them go off twice while trying to go, then not go off when he was finally done. It is not pleasant to have a toilet flush under you.
If there is anything to hang it from, a long strip of toilet tissue, hung down in front of the sensor eye, generally prevents this effect of premature flushing.
This is a good tip thanks!
I'm sensitive to loud noises and some public bathrooms have really, really, really loud and honestly just flat out aggressive toilets.
Only twice? That happens to me all the time. Maybe I will start covering up the sensor.
We used to carry around a pack of post-it notes to cover the sensors for this reason. My kids would refuse outright to use them otherwise.
I recommend a read of https://www.theguardian.com/society/2019/apr/25/hand-dryers-... which I found really interesting before committing to the anti hand dryer syndicate.
Kudos to the great research.
My kids hate the Dyson hand dryers. These things are incredibly loud.
My son (autistic and generally sensitive to noise) point-blank refuses to go into public toilets/restrooms just in case one goes off. :-(
I'm in exactly the same boat. To be honest, I've started to get twitchy whenever anyone uses one when he's NOT around, I'm that used to watching out for them.
Hand dryers. Leaf blowers. Hair dryers. Hoovers.
But bowling alleys and swimming pools are fine. I really want to figure out the spectrum of noise that hurts.
I've been sensitive to loud noises (still can't drive with my windows down) since I was a kid, and I've been diagnosed by a doctor to be on the spectrum (albeit high functioning) for various other reasons as well.
It's obviously different for everyone, but for me it comes down to a few things:
* Generally the higher pitch noises are way worse then a low deep "growl"
* Sudden, high decibel noises, especially if they're unexpected are BAD
* High decibel repetitive noises (ever have only one window open in your car on the highway and hear a WOMPH WOMPH WOMPH sound?) are unbearable.
* Restaurant buzzers, alarms, etc. Even the alarms coming from inside McDonalds while I'm in the drive through make me uncomfortable/
* Anything shrilly, no matter the decibel.
Sounds that are lower pitch, and continuous are much easier to get used to. The AC kicking on is uncomfortable, but after ~30 seconds the fan noise doesn't bother me.
For me public places have an "ambient sound" that seems to get filtered out okay. Mostly only the occasional small child skrill bothers me. I also have social anxiety so I'll get uncomfortable anyway however.
----
This seems to align with your observation that bowling alleys/swimming pools being okay. Most of the sounds are lower pitch, continuous, and most of the sudden noises are expected (kids splashing, bowling ball rolling, etc.)
The biggest difference is the decibel level though. Hand dryers. Leaf blowers. Hair dryers. Hoovers, are all LOUD.
Imagine your parents SCREAMING AS LOUD AS THEY CAN AT YOU. That's how those feel.
---
I have a feeling my observations will apply to most people on the spectrum, but you'd have to multiply it by 10x/100x depending on the severity of the individual.
I really want to figure out the spectrum of noise that hurts.
I suspect that, like most people in general, he's fine with lower-frequency sounds, but just more sensitive to high frequency ones.
Is he high enough function to manage his own over the ear hearing protection or does that raise issues of never getting them off of him?
I'd avoid in-ear until you know whether he'd just be leaving them always in which could cause its own problems.
He is high functioning enough for that. This is something we'll probably try down the line if things don't improve.
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!
I like the paper towel because I then have something to cleanly open the door with too.
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 think I’ve read somewhere that Sir Dyson was pro Brexit because of strict EU regulations. They moved their HQ to Singapore so it’s certainly not about the UK.
Their legal HQ has moved. The actual HQ is still in Malmesbury.
We have a set of kid sized ear-guards that my son prefer to wear when I vacuum with my Dyson vacuum cleaner. It's extremely loud and very srill (but it's also very effective).
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.
I’m sure mold grows in there because of the constant dampness. You can’t avoid touching the sides because the airflow is so strong and kind of forces it.
In the old days there was a multiple use towel than hung out of the dispensers and just circulated back in. Yuck.
https://collegeofcuriosity.com/2-18-restroom-evolution/
It was actually a roll of clean towel mechanically linked to a pickup roll of used towel, but it's much bulkier than paper towels so it faded away.
In many ways it's very similar to the change from cloth diapers to disposables.
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.
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.
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:
https://www.dyson.co.uk/hand-dryers/dyson-airblade-wash-dry-...
You can find these in some of the washrooms at Heathrow airport.
Soap and water does not fully kill the hand bacteria (which is good, kind of). And there are definitely possible problems with bacteria from those air dryers, see https://www.health.harvard.edu/blog/the-bacterial-horror-of-... - though there seems to be no real consensus here.
Modern hand dryer models, including Dyson air blades, do often have HEPA filters on their air intakes.
If you ever see an air blade in a less often cleaned public toilets there's usually pool of gunk at the bottom of the unit.
The musty smell that ensues when it's on makes me believe that the dirty dampness is being accelerated into a cloud of bacteria.
That is assuming that people actually wash their hands effectively, and also that the dryers themselves are not breeding areas for microbes.
I hate that thing. It's so loud. I refuse to dry my hands with it.
i am a bit confused by the problem here. if you decide to wash your hands and your face don't you get the same germs still on your hands onto your face?
if that is a problem then isn't the solution to wash hands more thouroughly?
on a side note, what concerns me much more is how many places i have to touch in a bathroom before even getting to the sink and start washing...
> what concerns me much more is how many places i have to touch in a bathroom before even getting to the sink and start washing..
Or worse, how many places you have to touch after you've washed, and when you've seen people leave who don't wash their hands.
in my experience it's easy to avoid having to touch anything at that point. most bathrooms in modern buildings i have seen are without doors.
ironically, not drying my hands after washing seems to help as i will make an effort not to touch anything until the hands are dry.
I have always wondered where the excess water/moisture goes to anyway. Most of them look absolutely disgusting.
There is no need for cursing on HN. Yes, the older models of Dyson Airblade were noisy, but they have addressed this in the latest model Dyson Airblade V HU02 which is significantly quieter.
Also, why are germs on your hands after washing them? Surely you used soap which killed 99.9% of germs and given that the Dyson Airblade V blows air downward, you would need to contort yourself to put your face below your hands ...
Dyson hand dryers blow air literally everywhere. And it’s not necessarily my germs it’s blowing, it’s the accumulated germs of everyone who’s used the dryer before me and touched the sides/dripped water into the unit.
Strong language is fine on HN as it is in adult dialogue generally. It is often very effective at conveying emotion and emphasis, which was the case here.
The HN guidelines prohibit personal attacks and political or ideological battle (which includes attacks or inflammatory commentaries on gender, nationality, race, etc).
But using a curse word to convey strong displeasure towards a product from a giant corporation seems fine to me.
You seem a little too upset because someone used a bad word.
No, we try to maintain better standards of dialogue here, and there is rarely a need to curse unless it's a quote from someone/something else.
I checked the guidelines and there is nothing against swearing or "standards of dialogue". FWIW swearing is within my standards of dialogue.
This seems to be a funny problem among some people, which also censor and beep each swear word in videos on YouTube or anywhere else. Seems to be some anticipatory obedience that is deeply embedded in some cultures/people.
I understand that different people and cultures have very different reactions to it, but profanity per se doesn't violate the HN guidelines.
The only reason to use a "bad word" is to make people upset. "Swearing is a weak mind trying to express itself forcefully."
newsflash: all hand blowers are nasty as fuck. Might as well just not wash your hands.
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.
I have very hard time to believe this. It can't be helpful to drive people away -- at least I don't use any hard driers anymore because of their noise levels.
I'd love for it not to be true and it's not like I have any proof
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.
Don't even get me started on leaf blowers and lawn edgers for totally unnecessary landscaping
Occasionally I'll check on how loud something is with my smartphone, and i'm always amazed at how loud some everyday things can get... especially when you factor in enclosed spaces.
So if I'm interpreting this right, solution 1, use towels for your kids if you can and solution 2, if there are no towels, hold your kid up and away so they are above the exit point of the air.
The Dyson blade driers (and their copy cats) are off limits to children anyway - they are not nearly tall enough to position hands inside them from above.
They’re building them into taps now
That's the strangest thing I've ever encountered in a washroom. It's bizarre and it's not obvious at all what to do with it.
It also makes everybody take twice as long at the sink, which is a problem in a high-traffic bathroom.
Makes things faster in my experience because it means there are as many driers as taps.
Which is an awful idea. Often times the dryer starting even before the water runs down.
Also it requires enough spacing not to blow onto the neighbor faucet(s).
I've used them a lot (used to work for Dyson, though not on the driers) and I'd say the taps are actually one of their best products. Have you actually used one?
It all depends on who's defining "best" and what their definition is.
> Have you actually used one?
Yeah, there are very common in the city I live.
That is an xkcd-worthy tragicomedy.
I wonder if using front trousers or shirt sides would be sanitary enough to be solution 1.5
i just let my hands dry naturally, and teach kids to do the same. as long as it's not freezing cold outside they will dry soon enough. it's the most environmental friendly too.
The transmission of bacteria is more likely to occur from wet skin than from dry skin[0]
[0]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3538484/
So you're the guy who gets the bathroom door handle wet, causing me to use twice the resources to wash my hands again, plus extra paper towels if available to dry off the handle.
nope, see my other replies, not touching the door handle with wet hands. if there is no way to get out without touching the handle i'll dry off first. i just won't if i know i can get away with out touching anything for a while
This was actually very "eye opening." I too used to be very sensitive to dryers in general but had since forgotten how painful they can be
This is so heartening to read about - and its easy to get started - May be I can 'encourage' my child to do a replication study :)
How valid is it to make a sound measurement in direct flow of air? I am not surprised that blowing air directly in to sound measurement device causes high reading, but is the tool designed for that. Isn't it the same as saying that pressure washer causes x decibels of noise when directed in to ear? Both will probably be damaging or unpleasant.
She measured sound levels at the ear, not in the airflow. She specifically mentions children being shorter and likely to stand closer to the noise source, and so made readings at multiple distances.
Interesting, I have actually noticed that some hand dryers are uncomfortably loud, especially the "special" high powered ones. Combine that with the struggle trying to activate the dryer, and keeping it activated while trying NOT to touch the surfaces, I can understand why some kids seemingly does not like them.
I've been avoiding hand dryers for years now. Mostly it's because a germaphobe friend pointed out years ago that germs are being blown onto your hand.
But after reading this I think my subconscious hates the noise it makes on my over-sensitive hearing.
The paper she published is at https://doi.org/10.1093/pch/pxz046
It's behind a paywall, but Sci-Hub works very nicely with a DOI…
Wow: "Several Dyson Airblade models were also very loud, including the single loudest measurement of 121 dBA"
I damaged my right ear-drum on a short-haul flight 20 years ago. I find hand-dryers almost painfully loud, and they rattle that ear-drum in an unpleasant way. Have often thought of doing dB measurements. Way to go, kid!
I can't stand anything past about 80db and I absolutely hate these things. Worst part is that there's no way to turn them off once they've been activated.
I would never consider using one of these. The annoying thing is when someone else walks into the bathroom and turns it on. Same for the disturbing, toxic – scented hand soap that is found in most bathrooms.
Paper towels every time
I regularly wear hearing protection when I visit the bigger city, and when I'm on public transit; even as an adult.
Out of interest, do you have a high sensitivity to noise around you?
I don't live in a particularly big city and when I visit bigger ones I do feel they are noisy. But not noisy enough to wear protection. I do wear protection when I'm on my motorcycle or at a concert or festival.
I can get by without protection, and it's not as though it particularly hurts; but I prefer things quieter, and it improves my mood. I often also wear it when I am working in an office environment with loud HVAC, also improves my mood.
I don't really know what would qualify as high sensitivity.
I also wear earplugs and they do improve my mood and ability to stay focused.
I remember that my father did the same when I was a kid. At that point I laughed, now I understand. I'm guessing sensitive ears run in the family.
Good on her for staying focused on the problem.
110 dB is 10 times louder than 100 dB.
where's the data?
The highest decibel things my kids are exposed to is themselves.
I have loud children, but they don't actually reach 110dB. I mean, YMMV, but I'd notice if there was something literally as loud as a rock concern in my basement or backyard.
Sure they do. I did a quick search and 110-130dB comes up on every result.
It's all about where you measure from, due to the inverse square law. For measuring things such as speakers for product specs, the standard is to measure from one meter away. But for rock concerts and hand dryers, you measure from the typical listening position.
I think you are considering your typical listening position for your child differently from the search results I found. If you were giving your kid a kiss goodnight and they screamed, it would be louder than if you were in the audience of a rock concert (but not louder than if you were kissing the concert speakers).
Every time you double the distance between the source and the meter, the meter reads 6dB lower.
Minor factoid: While that’s true in the limiting case (far away) for rock concerts, it’s common to use line arrays which fall -3 dB when you double your distance, as long as you’re within a certain range. Within this range they follow inverse rather than inverse square.
Very true. Most other things are approximately point sources, and even then it's unpredictable until you're at a sufficiently far field. And then there's free space, half-space (as with a wall mounted dryer), etc.
Is that a similar effect to antenna arrays?
It is most similar to the effect of electrostatic charges. The effect of a point charge is the inverse square of distance, the effect of a line charge is the inverse of distance, and the effect of an infinite plane has no relation to distance.
Ok thanks that is a useful mental model
It's more similar to an antenna that isn't an array. But you could compare an antenna array to a microphone array, sure. They both work by tweaking the phase and relative gain to arbitrarily change directivity without a need for physical directivity techniques. Like how home voice assistants and multi-antenna wifi APs achieve long distance reception without also amplifying 360 degrees of noise. They do a thing not unlike camera autofocus in that they quickly home in on whatever optimizes s/n.
Yeah, no joke. Kids shouting in your ear can cause permanent damage. I have a friend whose kid did that to them, and they now have problems hearing with that ear.
You're right. I should have specified that they don't put out the power of a rock concert.
Or one of these dryers, for that matter.
They are loud, but not as loud as one of these devices; not even close.
No worries, I know that's what you meant, and the point is that the power/intensity/volume/etc. at the source location really doesn't matter for this: at the listening position is what matters.
You're very likely some minimum distance from the speakers and from the dryer, but the minimum distance from your child could be nil (as in the 130dB claims) or significant (as in your experience), making it really hard to use something like a child in this conversation.
There’s also the tensor tympani muscle. I would assume that children tense it when shouting at full volume, which will somewhat reduce the effect.
That mitigates self-screaming, but not partner-screaming.
Mine did. My wife has permanent hearing loss from my daughter screaming in her ear. Years later she still says the best Mother’s Day present I ever gave her was a pair of gun mufflers.
can confirm this to be true
And I can corroborate.
I despise them due to the noise and length of time they take to dry hands.
I hate clickbait titles like this where there is no current age listed for comparison to the age referenced. Is the student 18 or 9.5? The time scale matters.
This reminds me of how Apple notoriously omits axis values during presentations just to make prettier-looking graphs.
> And the researcher, 13-year-old Nora Keegan, has been studying the issue since she was nine years old.