8 ms·

The bacterial horror of hot-air hand dryers (2018)

75 points by rascul 3y ago

hinkley 3y ago
If I ever build my own house, the plan (if code allows) is to not have a bathroom fan, and instead run the intake for an air exchanger into the bathroom. If I remodel this one I may well try to do the same. I think there's a reasonably good spot for it. Bathrooms, particularly public ones, are wet, mouldering places with insufficient ventilation. And we go into them every day to get ourselves clean. Taking air out of the bathroom and injecting it somewhere else is about the best way I can think of to fix that, and we only run them intermittently.
- DontchaKnowit 3y ago
  Wait you want to redistribute shit air to the rest of the house? Im not understanding this proposal
  - paulmd 3y ago
    I think the implication is he wants to run industrial air-changers 24/7, basically turning his bathroom into a fume-hood, and then venting it outside. So, same idea as bathroom fan but really big and running it less intermittently. He wants a big industrial air-changer so his bathroom is less dank. One problem is this will definitely suck a lot of heat out of the house. You might want to only run it when a sensor detects humidity, and just give it a ton of hysterisis/etc so that it runs a relatively long time. Pulling a bunch of heat out of your house 24/7 will be expensive and will cause other problems (like extreme low humidity since the furnace is running much more, which will lead to crazy amounts of static etc). You can of course run a humidifier (or whole-house humidifier) etc but it's generally not without problems to just dump air 24/7. (I had similar sentiments around my current house not having good air handling for the stove, if you are frying something it can get pretty greasy/nasty inside even with the fan on, and you can't always open a window depending on the weather.) On the other hand, this also might help with CO2/oxygen levels, which might lead to better overall health/comfort too, because your air is being cycled more aggressively. The overall thrust that houses are getting too airtight nowadays is generally correct, and this has negative health effects too. It is, again, unfortunately balanced against heating costs (energy efficiency seals the house up, then we circulate the air out...) and other problems. If the house is super breezy (or has air changers aggressively changing the air) then you're also pumping out all your heat and humidity. If you are going to have some strong air changers though, you could run a heat pump in the air changer stage too. Being able to spend 1 unit of energy to move 10 units of heat from the exhaust back to the intake would be ideal, and the air is going outside anyway so you might as well dump waste cold (or waste heat, in the summer) outside while you're doing it. An easier step, if you have the space in your bathroom, would just be to run a dehumidifier in the bathroom. Obviously would be pointless/inefficient during a shower, but maybe you could have a switch where one pole is "bathroom fan on" and the other one is "dehumidifier on". Or get a timer switch and just run it for an hour after the shower is done. It is also worth noting that if you get the humidity under control in general, that the house itself will act as an "anchor" and tend to resist changes from the mean. The bathroom is dank because all the building materials around it are saturated and constantly giving off water, if you can keep it at 40-50% humidity more regularly then eventually they will dry out and the system stabilizes at a less-dank humidity.
    - keep_reading 3y ago
      That's what an ERV is designed to handle. They're becoming code in some places https://www.aprilaire.com/whole-house-products/ventilation/model-8100 https://www.aprilaire.com/whole-house-products/ventilation/m...
      - wombatpm 3y ago
        My house in Minnesota had one. The building codes were such that the first winter without we had constant condensation on the windows, which ruined the finish. Installed one later that did 4 whole house air exchanges per hour. Best investment ever.
    - hinkley 3y ago
      I first encountered consumer grade versions of these on This Old House. I’m not sure when, but I stopped watching it regularly probably twenty years ago, so at least fifteen? At the time dust collection systems were still pretty exotic, so they were putting them into wood shops to make sure the dust didn’t get sucked into the rest of the house.
  - keep_reading 3y ago
    Maybe install the ERV/HRV return vent into his bathroom wall? https://www.aprilaire.com/whole-house-products/ventilation/model-8100 https://www.aprilaire.com/whole-house-products/ventilation/m...
    - hinkley 3y ago
      That’s exactly what I’m taking about. Downvoters seem to not know these have existed for thirty years.
  - Izkata 3y ago
    They said "If I ever build my own house" - I think the idea is to prevent it from becoming "shit air" in the first place by having the air exchange there from the beginning.
    - manwe150 3y ago
      I think they meant “shit air” literally. As in, it doesn’t just smell like farts, it is actual farts, being proposed to be blown throughout the rest of the house
      - deleted 3y ago
        [deleted]
  - hinkley 3y ago
    What is wrong with everyone today (yesterday)? Does nobody hear know what an air/heat exchanger does? They’re for ventilating modern sealed construction so you don’t choke to death on fumes from your belongings, or get cancer from your wood shop.
- Arrath 3y ago
  Isn't the solution to have a bathroom fan that vents to the ouside?
  - xeromal 3y ago
    Pretty sure bathroom fans DO vent to the outside. At least in homes here in the US.
    - spondylosaurus 3y ago
      They do in modern homes: > If you're a homeowner, be sure that your fan is properly vented directly to the home's exterior via an insulated duct. "It was common in the '70s and '80s for it to be vented into the attic space," says Bayne. "Building codes today require that the exhaust is vented outside through insulated ducting to a roof vent that goes directly to the exterior." Otherwise, you may be contributing to moisture and mold problems in your attic or wall spaces. https://home.howstuffworks.com/bathroom-exhaust-fan.htm https://home.howstuffworks.com/bathroom-exhaust-fan.htm Related, but I like how kitchen exhausts sometimes come out of a vent on the side of the house, so if you go out into the backyard you can walk by and smell bacon frying or whatever. (OTOH I once lived in a condo with an under-the-microwave exhaust that didn't actually vent outside, it just spat everything up onto the kitchen ceiling... a wet greasy spot accumulated up there before I realized what was going on.)
      - mumblemumble 3y ago
        Hey, at least they gave you that kindness. At the last place I lived, it was configured to spray everything all over the inside of the cabinet above the microwave.
        spondylosaurus 3y ago
        Augh, that's horrible. I can only imagine the scene inside that cabinet...
        userbinator 3y ago
- thsksbd 3y ago
  I run my bathroom fan for hours after I shower. Drywall is a sponge after all
  - sonofhans 3y ago
    Not painted properly, it isn’t. Moisture protection is one of the primary benefits of paint.
    - thsksbd 3y ago
      Unless you're using a speciality paint, latex is too porous (for vapor, not liquid water) and gypsum too large a chemical potential well.
      - sonofhans 3y ago
        Yeah, “properly” was doing some work in my response :) It helps to use a glossy paint, and to put that over wet-environment primer on top of wet-environment drywall.
        thsksbd 3y ago
        Cool. Rhanks for the reply
- sonofhans 3y ago
  No hate, and good on you for thinking about it deeply, but this is a terrible idea. The primary thing you want to exhaust from bathrooms is humidity. You want the shortest, straightest path out of the house for that 100% humid air. Recirculating it will create untold horrors of mold all the way downstream of the bathroom. It’s also unlikely to be allowed by residential building codes, or passed by any inspector.
  - hinkley 3y ago
    That’s not how heat exchangers work.
    - sonofhans 3y ago
      I’m not sure you’re replying to the right comment. I didn’t mention heat exchangers, only air movement, replying to you talking about “air exchange.”
blueridge 3y ago
I don't use the hot-air hand dryers because they physically hurt my ears. They're so damn loud. I don't know which one is worse, the Dyson Airblade or the Xcelerator.
- xeromal 3y ago
  I thought the same thing but someone told me that was autism so I just keep my mouth shut. lol
  - arp242 3y ago
    Someone went around measuring volume levels, and found that all were louder than 100 dBA, with the loudest being 121 dBA! These are beyond "a tad annoying" and into "hearing damage". https://academic.oup.com/pch/article-abstract/25/4/216/5519522?redirectedFrom=fulltext https://academic.oup.com/pch/article-abstract/25/4/216/55195...
    - atoav 3y ago
      Measured at what distance? I just measured 120 dBA blowing into the mic next to my sleeping girlfriend without her waking up. Not to question the results, but methodology is important.
      - Gigachad 3y ago
        The time period matters as well. Just clicking your fingers is loud enough to give you hearing damage if sustained for 30 minutes. I would not at all be worried about hand dryers unless you sat next to one all day.
        pests 3y ago
        > clicking Snapping? Or is this a new fad I don't know about?
        3y ago
spondylosaurus 3y ago
These hot germ rockets are bad enough on their own, and then they also deprive you of a nice clean paper towel to open the bathroom door with on your way out. Barbarous!
- I_Am_Nous 3y ago
  I have been known to pull my Leatherman out of my pocket and use that to touch the door handle if possible. I'll do just about anything to not have to touch the door handle.
  - kijin 3y ago
    Bidirectionally pushable doors for the win! You can just push with your foot.
    - TeMPOraL 3y ago
      You can also pull with your foot. It's something you learn if you really don't want to touch those door handles.
    - jszymborski 3y ago
      Even better, the serpentine entrances to washrooms that don't even require a door
standardUser 3y ago
It seems like I could go to great lengths to be a germaphobe and take extraordinary precautions at every turn, or I could not do that at all and just wing it, and either way I will get between one and two mild-to-moderate head colds every year. And this is in NYC where I spend half my life in crowded spaces. Just doesn't seem worth the hassle to give a shit.
- deleted 3y ago
  [deleted]
- Scoundreller 3y ago
  Are you wearing N95s everywhere or just focussing on hand hygiene? I thought COVID busted the whole “wash your hands to avoid the flu” thing for viral respiratory diseases.
  - _yb2s 3y ago
    No, covid does not often spread that way but a large number of other common viruses do.
    - Scoundreller 3y ago
      Which viral respiratory ones? I thought most of them (influenza, parainfluenza, RSV and all the other coronaviruses) were enveloped viruses like covid-19. I guess adenoviruses would be the exception.
      - _yb2s 3y ago
        Look up “fomite transmission.” Rhinovirus colds do transmit that way. Most are also transmitted by aerosols, so you are correct in that… people were wrong that thought you could virtually eliminate virus transmission by just washing your hands a lot.
      - melagonster 3y ago
        for example, https://en.m.wikipedia.org/wiki/Norovirus https://en.m.wikipedia.org/wiki/Norovirus alcohol can not kill everything.
srcreigh 3y ago
> The vast majority of the microbes that were detected do not cause disease in healthy people, with the exception of Staphylococcus aureus. Some of the bathroom bacteria, such as Acinetobacter, only cause infections in people in the hospital, or in those with weak immune systems. The others that were found are relatively harmless. > In addition, air from real-world bathrooms may contain fewer bacteria than the bathrooms in the study. The sampled restrooms were located in a university health sciences building, and at least some of the bacteria came from experiments going on in laboratories within the building.
- Scoundreller 3y ago
  On the topic of unfortunate mingling with research, for an AIDS drug, ritonavir, it can come in multiple crystalline forms. But this was unknown. For years manufacturers only knew about and produced “Form 1” without issue for years until “Form 2” showed up out of nowhere. Maybe from a lab studying it, who knows. But once it’s out, as it’s more stable, it’s preferred! It “infected” a key manufacturing plant with it, and the batches kept showing up in that form. And cleaning it away is virtually impossible. > And Form Two went everywhere. Within days of identifying Form Two, the company’s analytical lab could only make that form of the drug. The bulk drug coming off the production line in Chicago turned out to be contaminated before it ever went in to the capsules. Staff from Chicago were sent to an uncontaminated production line in Italy to find out if they were doing anything differently. Within weeks, that line was producing Form Two as well. As it’s more stable, it means it doesn’t dissolve as well, but is also favoured. That’s bad news if you want a pill that dissolves in your stomach (or in this case, in the liquid capsules), or need an injectable solution. https://www.chemistryworld.com/podcasts/ritonavir/4011593.article https://www.chemistryworld.com/podcasts/ritonavir/4011593.ar... The (fear-mongering chaser?): > This wasn’t the first drug to show unexpected polymorphism. And it certainly wouldn’t be the last. Research published in 2018 suggests that a more stable polymorph is waiting to be created for about fifteen to fifty percent of all drugs.
  - s1artibartfast 3y ago
    My skepticism has turned to wonder. here are the technical details: https://cmbe.engr.uga.edu/bche4520/Other/Ch9/Bauer%202001.pdf https://cmbe.engr.uga.edu/bche4520/Other/Ch9/Bauer%202001.pd...
tapanjk 3y ago
I find them useless simply because it takes way too long to dry the hands completely. A handkerchief or a tissue does the job in a second. Also, maybe it's just me, but I find my palms a bit sticky after drying them with hot air.
fnordpiglet 3y ago
“Fecal cloud” made the article worth the read. New vocabulary.
kijin 3y ago
If the germs are from the same air that you're breathing and moving around in, and not growing inside the dryer or particularly concentrated in any way, I don't see what the problem is. The same germs will be found on the surface of paper towels or any other object in the bathroom. The article mentions attaching HEPA filters to hand dryers, but that sounds like a terrible idea since bathrooms are often humid. A wet filter quickly becomes a breeding ground for mold. If you really want to turn your hand dryer into an air sanitizer, how about ensuring that at some point during the air's passage through the machine, it reaches a temperature high enough to kill germs? (Cool it down a bit before it reaches the exhaust, of course.) Or maybe install a UVC lamp inside? These tricks will require a larger and much more expensive machine, though.
caymanjim 3y ago
I know this sounds gross, and people will have a knee-jerk negative reaction to it, but washing your hands at all in many public bathrooms is pretty nasty. I guarantee my <encrypted> is far, far, far cleaner than anything I'd touch in a public restroom. If there's a sink faucet that needs to be manually turned on and off, that's going to be infested with bacteria. If it's a no-touch faucet, then there's no downside to washing (so long as you don't touch the rest of the sink), but I've always felt that all those air-blasting dryers were just blasting bacteria all over the place. I always wash my hands, because societal norms strongly discourage any alternative. But I have no illusions about the fact that I'm picking up more bacteria half the time. If there are no paper towels to dry, I'll almost always just shake the water off and dry my hands on my pants instead. Beyond the bacteria-blasting, I find that hot air dryers take way too long and still leave my hands damp anyway. And if you touch the door handle on your way out, you've thoroughly undone any cleaning you may have just performed. Thankfully I'm not a germophobe, so I follow societal norms and wash lest I'm called out on it, and don't actively think about any of this.
- thanksgiving 3y ago
  I don’t have any education or training in these things so take whatever I’m saying with a huge grain of salt but I thought the point of washing hands was not to get rid of bacteria themselves but the oils naturally occurring in our hands so that bacteria has a harder time sticking to the skin on our hands?
  - wanderingstan 3y ago
    Also not a pro, but I’m pretty sure the point is for the soap to rupture/destroy bacteria and viruses. See: https://medicine.yale.edu/news-article/why-soap-works/ https://medicine.yale.edu/news-article/why-soap-works/
sriram_malhar 3y ago
Much ado about nothing? If there are so many bacteria already milling about in the air, you'd have already breathed in billions (?) of them before you got to the dryer. If you are not immunocompromised, you do yourself a disservice by being so worried about bacteria. I don't bother with attempting to avoid or prevent that might merely inconvenience you for a while but is eminently treatable at home (flu, for example).

75 points by rascul 3y ago

If I ever build my own house, the plan (if code allows) is to not have a bathroom fan, and instead run the intake for an air exchanger into the bathroom. If I remodel this one I may well try to do the same. I think there's a reasonably good spot for it. Bathrooms, particularly public ones, are wet, mouldering places with insufficient ventilation. And we go into them every day to get ourselves clean. Taking air out of the bathroom and injecting it somewhere else is about the best way I can think of to fix that, and we only run them intermittently.

DontchaKnowit 3y ago
Wait you want to redistribute shit air to the rest of the house? Im not understanding this proposal
- paulmd 3y ago
  I think the implication is he wants to run industrial air-changers 24/7, basically turning his bathroom into a fume-hood, and then venting it outside. So, same idea as bathroom fan but really big and running it less intermittently. He wants a big industrial air-changer so his bathroom is less dank. One problem is this will definitely suck a lot of heat out of the house. You might want to only run it when a sensor detects humidity, and just give it a ton of hysterisis/etc so that it runs a relatively long time. Pulling a bunch of heat out of your house 24/7 will be expensive and will cause other problems (like extreme low humidity since the furnace is running much more, which will lead to crazy amounts of static etc). You can of course run a humidifier (or whole-house humidifier) etc but it's generally not without problems to just dump air 24/7. (I had similar sentiments around my current house not having good air handling for the stove, if you are frying something it can get pretty greasy/nasty inside even with the fan on, and you can't always open a window depending on the weather.) On the other hand, this also might help with CO2/oxygen levels, which might lead to better overall health/comfort too, because your air is being cycled more aggressively. The overall thrust that houses are getting too airtight nowadays is generally correct, and this has negative health effects too. It is, again, unfortunately balanced against heating costs (energy efficiency seals the house up, then we circulate the air out...) and other problems. If the house is super breezy (or has air changers aggressively changing the air) then you're also pumping out all your heat and humidity. If you are going to have some strong air changers though, you could run a heat pump in the air changer stage too. Being able to spend 1 unit of energy to move 10 units of heat from the exhaust back to the intake would be ideal, and the air is going outside anyway so you might as well dump waste cold (or waste heat, in the summer) outside while you're doing it. An easier step, if you have the space in your bathroom, would just be to run a dehumidifier in the bathroom. Obviously would be pointless/inefficient during a shower, but maybe you could have a switch where one pole is "bathroom fan on" and the other one is "dehumidifier on". Or get a timer switch and just run it for an hour after the shower is done. It is also worth noting that if you get the humidity under control in general, that the house itself will act as an "anchor" and tend to resist changes from the mean. The bathroom is dank because all the building materials around it are saturated and constantly giving off water, if you can keep it at 40-50% humidity more regularly then eventually they will dry out and the system stabilizes at a less-dank humidity.
  - keep_reading 3y ago
    That's what an ERV is designed to handle. They're becoming code in some places https://www.aprilaire.com/whole-house-products/ventilation/model-8100 https://www.aprilaire.com/whole-house-products/ventilation/m...
    - wombatpm 3y ago
      My house in Minnesota had one. The building codes were such that the first winter without we had constant condensation on the windows, which ruined the finish. Installed one later that did 4 whole house air exchanges per hour. Best investment ever.
  - hinkley 3y ago
    I first encountered consumer grade versions of these on This Old House. I’m not sure when, but I stopped watching it regularly probably twenty years ago, so at least fifteen? At the time dust collection systems were still pretty exotic, so they were putting them into wood shops to make sure the dust didn’t get sucked into the rest of the house.
- keep_reading 3y ago
  Maybe install the ERV/HRV return vent into his bathroom wall? https://www.aprilaire.com/whole-house-products/ventilation/model-8100 https://www.aprilaire.com/whole-house-products/ventilation/m...
  - hinkley 3y ago
    That’s exactly what I’m taking about. Downvoters seem to not know these have existed for thirty years.
- Izkata 3y ago
  They said "If I ever build my own house" - I think the idea is to prevent it from becoming "shit air" in the first place by having the air exchange there from the beginning.
  - manwe150 3y ago
    I think they meant “shit air” literally. As in, it doesn’t just smell like farts, it is actual farts, being proposed to be blown throughout the rest of the house
    - deleted 3y ago
      [deleted]
- hinkley 3y ago
  What is wrong with everyone today (yesterday)? Does nobody hear know what an air/heat exchanger does? They’re for ventilating modern sealed construction so you don’t choke to death on fumes from your belongings, or get cancer from your wood shop.
Arrath 3y ago
Isn't the solution to have a bathroom fan that vents to the ouside?
- xeromal 3y ago
  Pretty sure bathroom fans DO vent to the outside. At least in homes here in the US.
  - spondylosaurus 3y ago
    They do in modern homes: > If you're a homeowner, be sure that your fan is properly vented directly to the home's exterior via an insulated duct. "It was common in the '70s and '80s for it to be vented into the attic space," says Bayne. "Building codes today require that the exhaust is vented outside through insulated ducting to a roof vent that goes directly to the exterior." Otherwise, you may be contributing to moisture and mold problems in your attic or wall spaces. https://home.howstuffworks.com/bathroom-exhaust-fan.htm https://home.howstuffworks.com/bathroom-exhaust-fan.htm Related, but I like how kitchen exhausts sometimes come out of a vent on the side of the house, so if you go out into the backyard you can walk by and smell bacon frying or whatever. (OTOH I once lived in a condo with an under-the-microwave exhaust that didn't actually vent outside, it just spat everything up onto the kitchen ceiling... a wet greasy spot accumulated up there before I realized what was going on.)
    - mumblemumble 3y ago
      Hey, at least they gave you that kindness. At the last place I lived, it was configured to spray everything all over the inside of the cabinet above the microwave.
      - spondylosaurus 3y ago
        Augh, that's horrible. I can only imagine the scene inside that cabinet...
      - userbinator 3y ago
thsksbd 3y ago
I run my bathroom fan for hours after I shower. Drywall is a sponge after all
- sonofhans 3y ago
  Not painted properly, it isn’t. Moisture protection is one of the primary benefits of paint.
  - thsksbd 3y ago
    Unless you're using a speciality paint, latex is too porous (for vapor, not liquid water) and gypsum too large a chemical potential well.
    - sonofhans 3y ago
      Yeah, “properly” was doing some work in my response :) It helps to use a glossy paint, and to put that over wet-environment primer on top of wet-environment drywall.
      - thsksbd 3y ago
        Cool. Rhanks for the reply
sonofhans 3y ago
No hate, and good on you for thinking about it deeply, but this is a terrible idea. The primary thing you want to exhaust from bathrooms is humidity. You want the shortest, straightest path out of the house for that 100% humid air. Recirculating it will create untold horrors of mold all the way downstream of the bathroom. It’s also unlikely to be allowed by residential building codes, or passed by any inspector.
- hinkley 3y ago
  That’s not how heat exchangers work.
  - sonofhans 3y ago
    I’m not sure you’re replying to the right comment. I didn’t mention heat exchangers, only air movement, replying to you talking about “air exchange.”

blueridge 3y ago

I don't use the hot-air hand dryers because they physically hurt my ears. They're so damn loud. I don't know which one is worse, the Dyson Airblade or the Xcelerator.

xeromal 3y ago
I thought the same thing but someone told me that was autism so I just keep my mouth shut. lol
- arp242 3y ago
  Someone went around measuring volume levels, and found that all were louder than 100 dBA, with the loudest being 121 dBA! These are beyond "a tad annoying" and into "hearing damage". https://academic.oup.com/pch/article-abstract/25/4/216/5519522?redirectedFrom=fulltext https://academic.oup.com/pch/article-abstract/25/4/216/55195...
  - atoav 3y ago
    Measured at what distance? I just measured 120 dBA blowing into the mic next to my sleeping girlfriend without her waking up. Not to question the results, but methodology is important.
    - Gigachad 3y ago
      The time period matters as well. Just clicking your fingers is loud enough to give you hearing damage if sustained for 30 minutes. I would not at all be worried about hand dryers unless you sat next to one all day.
      - pests 3y ago
        > clicking Snapping? Or is this a new fad I don't know about?
        3y ago

spondylosaurus 3y ago

These hot germ rockets are bad enough on their own, and then they also deprive you of a nice clean paper towel to open the bathroom door with on your way out. Barbarous!

I_Am_Nous 3y ago
I have been known to pull my Leatherman out of my pocket and use that to touch the door handle if possible. I'll do just about anything to not have to touch the door handle.
- kijin 3y ago
  Bidirectionally pushable doors for the win! You can just push with your foot.
  - TeMPOraL 3y ago
    You can also pull with your foot. It's something you learn if you really don't want to touch those door handles.
  - jszymborski 3y ago
    Even better, the serpentine entrances to washrooms that don't even require a door

standardUser 3y ago

It seems like I could go to great lengths to be a germaphobe and take extraordinary precautions at every turn, or I could not do that at all and just wing it, and either way I will get between one and two mild-to-moderate head colds every year. And this is in NYC where I spend half my life in crowded spaces. Just doesn't seem worth the hassle to give a shit.

deleted 3y ago
[deleted]
Scoundreller 3y ago
Are you wearing N95s everywhere or just focussing on hand hygiene? I thought COVID busted the whole “wash your hands to avoid the flu” thing for viral respiratory diseases.
- _yb2s 3y ago
  No, covid does not often spread that way but a large number of other common viruses do.
  - Scoundreller 3y ago
    Which viral respiratory ones? I thought most of them (influenza, parainfluenza, RSV and all the other coronaviruses) were enveloped viruses like covid-19. I guess adenoviruses would be the exception.
    - _yb2s 3y ago
      Look up “fomite transmission.” Rhinovirus colds do transmit that way. Most are also transmitted by aerosols, so you are correct in that… people were wrong that thought you could virtually eliminate virus transmission by just washing your hands a lot.
    - melagonster 3y ago
      for example, https://en.m.wikipedia.org/wiki/Norovirus https://en.m.wikipedia.org/wiki/Norovirus alcohol can not kill everything.

srcreigh 3y ago

> The vast majority of the microbes that were detected do not cause disease in healthy people, with the exception of Staphylococcus aureus. Some of the bathroom bacteria, such as Acinetobacter, only cause infections in people in the hospital, or in those with weak immune systems. The others that were found are relatively harmless. > In addition, air from real-world bathrooms may contain fewer bacteria than the bathrooms in the study. The sampled restrooms were located in a university health sciences building, and at least some of the bacteria came from experiments going on in laboratories within the building.

Scoundreller 3y ago
On the topic of unfortunate mingling with research, for an AIDS drug, ritonavir, it can come in multiple crystalline forms. But this was unknown. For years manufacturers only knew about and produced “Form 1” without issue for years until “Form 2” showed up out of nowhere. Maybe from a lab studying it, who knows. But once it’s out, as it’s more stable, it’s preferred! It “infected” a key manufacturing plant with it, and the batches kept showing up in that form. And cleaning it away is virtually impossible. > And Form Two went everywhere. Within days of identifying Form Two, the company’s analytical lab could only make that form of the drug. The bulk drug coming off the production line in Chicago turned out to be contaminated before it ever went in to the capsules. Staff from Chicago were sent to an uncontaminated production line in Italy to find out if they were doing anything differently. Within weeks, that line was producing Form Two as well. As it’s more stable, it means it doesn’t dissolve as well, but is also favoured. That’s bad news if you want a pill that dissolves in your stomach (or in this case, in the liquid capsules), or need an injectable solution. https://www.chemistryworld.com/podcasts/ritonavir/4011593.article https://www.chemistryworld.com/podcasts/ritonavir/4011593.ar... The (fear-mongering chaser?): > This wasn’t the first drug to show unexpected polymorphism. And it certainly wouldn’t be the last. Research published in 2018 suggests that a more stable polymorph is waiting to be created for about fifteen to fifty percent of all drugs.
- s1artibartfast 3y ago
  My skepticism has turned to wonder. here are the technical details: https://cmbe.engr.uga.edu/bche4520/Other/Ch9/Bauer%202001.pdf https://cmbe.engr.uga.edu/bche4520/Other/Ch9/Bauer%202001.pd...

tapanjk 3y ago

I find them useless simply because it takes way too long to dry the hands completely. A handkerchief or a tissue does the job in a second. Also, maybe it's just me, but I find my palms a bit sticky after drying them with hot air.

fnordpiglet 3y ago

“Fecal cloud” made the article worth the read. New vocabulary.

kijin 3y ago

If the germs are from the same air that you're breathing and moving around in, and not growing inside the dryer or particularly concentrated in any way, I don't see what the problem is. The same germs will be found on the surface of paper towels or any other object in the bathroom. The article mentions attaching HEPA filters to hand dryers, but that sounds like a terrible idea since bathrooms are often humid. A wet filter quickly becomes a breeding ground for mold. If you really want to turn your hand dryer into an air sanitizer, how about ensuring that at some point during the air's passage through the machine, it reaches a temperature high enough to kill germs? (Cool it down a bit before it reaches the exhaust, of course.) Or maybe install a UVC lamp inside? These tricks will require a larger and much more expensive machine, though.

caymanjim 3y ago

I know this sounds gross, and people will have a knee-jerk negative reaction to it, but washing your hands at all in many public bathrooms is pretty nasty. I guarantee my <encrypted> is far, far, far cleaner than anything I'd touch in a public restroom. If there's a sink faucet that needs to be manually turned on and off, that's going to be infested with bacteria. If it's a no-touch faucet, then there's no downside to washing (so long as you don't touch the rest of the sink), but I've always felt that all those air-blasting dryers were just blasting bacteria all over the place. I always wash my hands, because societal norms strongly discourage any alternative. But I have no illusions about the fact that I'm picking up more bacteria half the time. If there are no paper towels to dry, I'll almost always just shake the water off and dry my hands on my pants instead. Beyond the bacteria-blasting, I find that hot air dryers take way too long and still leave my hands damp anyway. And if you touch the door handle on your way out, you've thoroughly undone any cleaning you may have just performed. Thankfully I'm not a germophobe, so I follow societal norms and wash lest I'm called out on it, and don't actively think about any of this.

thanksgiving 3y ago
I don’t have any education or training in these things so take whatever I’m saying with a huge grain of salt but I thought the point of washing hands was not to get rid of bacteria themselves but the oils naturally occurring in our hands so that bacteria has a harder time sticking to the skin on our hands?
- wanderingstan 3y ago
  Also not a pro, but I’m pretty sure the point is for the soap to rupture/destroy bacteria and viruses. See: https://medicine.yale.edu/news-article/why-soap-works/ https://medicine.yale.edu/news-article/why-soap-works/

sriram_malhar 3y ago

Much ado about nothing? If there are so many bacteria already milling about in the air, you'd have already breathed in billions (?) of them before you got to the dryer. If you are not immunocompromised, you do yourself a disservice by being so worried about bacteria. I don't bother with attempting to avoid or prevent that might merely inconvenience you for a while but is eminently treatable at home (flu, for example).