An air purifier is the best noise machine for me, much better than the white noise machines with the tinny speakers. Even the brown noise setting on those isn't nearly deep enough to let me sleep.
Yea, having it and using it at max just as I go to bed just makes me feel much better for the air I'll be breathing while sleeping. I also used to always fall asleep to some noise or music, so this is such a nice replacement
I have 4 Coway and 2 Winix purifiers and I can confirm: they're great sleep noise generators! The plastic front pieces and the filters themselves block/baffle any high frequency noise from the fans, leaving you with a pleasant low/mid frequency whooooooosh. I like it better than the sound from small cheap solid state machines; their small speakers can't do low frequencies.
For most circumstances where someone would use
a white noise machine, this kind of small purifier
is all-around better.
Hmm. The word "most" is doing a lot of work here.
Depends if you enjoy fresh air when you sleep or not. If you've ever monitored CO2 levels you know how quickly they climb in a closed room.
But, if you are blowing fresh air into a room, or have the windows open, the filtration effectiveness of these units approaches zero pretty rapidly. And these air purifiers aren't exactly free to run: they use ~50-100W of power and if you run them 24/7 you can expect to spend $100+ per year on filters.
None of those seem particularly concerning. We have a gas range, and 15 min past the end of cooking everything is fine. I must imagine that most people don't live right next to the freeway so they probably have even better air quality except during wildfire season.
CO2 - I'm thrilled with anything less than 800 ppm (half justified by being the lowest number I've ever seen a study suggest might have health effects, half justified by being at a point where I personally don't notice that I'm more drowsy).
PM2.5 - My impression is the health risks here are more cumulative exposure (and include things I'd like to go without in my life, like alzheimers) and a pretty straight line of "lower is better all the way to zero". The WHO's guideline is mean exposure of 5 µg/m³ so I guess I'd adopt that if I had to put a number on it. (But it's a mean, I wouldn't worry about briefly exceeding it)
PM10 - No real opinion (I'd rather worry about PM2.5)
VOC index - I'm not sure this is a standardized thing, but the version I've come across is an index relative to the average that particular sensor has seen in the last 24 hours. So there's no standard possible here.
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As for a gas range I would worry about NOX considering the studies with them causing and aggravating asthma. That said your CO2 levels are low so I suspect you might have sufficient ventilation that this isn't a huge issue for you (especially if that ventilation is in the form of a fume hood over your stove that you actually use).
This makes me wonder, for a truly travel-size solution (or just otherwise compact needs), if there's a viable alternative that directs filtered air at a sleeper's head? In other words, would the net effect be equivalent for one person (such that they're breathing more or less the same cleanness of air)?
I grasp that such an approach might draw unfiltered surrounding air along with the filtered stream of air, and imagine that it would likely be easily overwhelmed by a steady supply of exceptionally polluted air (wildfire smoke or simply a heavily polluted urban area), but I still would be interested in knowing if the compromise never overcomes a level of placebo effect, or if there's a point where it actually achieves measurable benefit (both in efficacy and portability—like a even more compact and directional version of the Corsi-Rosenthal computer fan solution.)
I have seen models designed this way! Vornado used to make one, I think it's discontinued.
These directed-air "personal models" make a lot of sense to me... at least in theory. I haven't seen them properly tested.
The big air purifiers work great.. if the room is closed up. But their effectiveness approaches zero if you have the windows open or otherwise have unfiltered air entering the room. Which is kind of important, if you don't enjoy breathing in sky high levels of CO2. (If one's allergies are bad enough, or a wildfire is raging outside, CO2 might of course be preferable to particulates)
I bought a large soldering iron air purifier and it turns out to be great; it has a continuious speed selector, easy to replace filters, and very pleasant spectrum. I like it better than the air conditioner, which cycles on and off noisily.
Filters are included, as well as high quality fans, AC/DC converter and speed controller, and the portable/collapsible enclosure. It's really not that expensive vs trying to put together the parts yourself, and it's tested to work very well compared to other more expensive filters.
Those fans will not have sufficient static pressure to be useful. These makeshift purifiers may be great in a pinch (wildfire season and stores are all out), but far from the best.
This is indeed the "conventional wisdom," but if you do the math it turns out this is incorrect.
The trick is to use high-airflow MERV 13 filters (ideally 3M 1900, which has high pleat count and low resistance) instead of high-resistance HEPA filters, so axial PC fans can generate enough pressure.
Merv-13 means it filters at least 75% of the particles passing through it.
For a standalone air filter which is pushing the filtered air into the same room its drawing from, we can assume reasonably good mixing of the intake and exhaust air. Thus to be equivalent to a HEPA-filter it only needs 1/3rd more airflow... Which really isn't much.
This doesn't follow for a a fancier setup where you're taking dirty air and blowing it into a cleanroom or something... but that's not how we're typically using household air filters.
The linked PC-fan purifier has been tested and shown to purify air faster than the conventional alternatives, and are not makeshift, so I'm not sure what you are referring to.
From the specs it looks like they are probably closer to higher-static-pressure server fans, the CADR is a few hundred CFM and it pulls 30+ watts. And as with many of these designs, you can compensate for low pressure performance by increasing filter surface area... the greater the surface area the lower the pressure drop. Of course, the problem with this is you are just spending more money on filters, which is the expensive part.
The filter cost for the AirFanta 3 doesn't seem particularly high? In fact it seems cheaper than competitors.
All the purifier companies realized they make more money selling overpriced filters, so $60+ for the OEM filters is common nowadays. Despite it just being a standard HEPA filter cut to a specific size.
Airfanta 3 Pro filters (four) - $57
Coway Mighty Filter - $60
Coway Mighty2 Filter - $70-$80
I'd be concerned about the availability of filters after a few years. Some of these companies have been changing their models and filter type every year to add some nebulous feature. Others just go out of business.
Yeah, the retail prices of filters is all over the place because of the popularity of razor/blade model of pricing. I'm not talking about that, I'm talking about the BOM itself -- this device is using 4x the filter media of comparable filters, which would typically have one filter that size.
HEPA media itself is a commodity and aftermarket filters (and the BOM cost) tend to level out at whatever rate is minimally profitable per area of filter media.
The upfront cost of this device is high for what you get, because you're mostly buying filter media. The device itself is not much of a polished product. I'm sure it works fine but I wouldn't want one in my living room.
I have one in the bedroom. On low, I barely hear it during the day (extra ambient noise from outside) but at night the white-noise is subtle but effective. That said, I don't like "loud" white noise, just a quiet hum.
YSK on low you won't be getting much air cleaning power. All air purifiers are rated based on their top fan speed.
Housefresh, which is a criminally underrated review channel btw, recently did a comparison of PC fans for this purpose. The Thermalright TL-14C family came out strong in the "Silent" category, with the best ultra-quiet 24/7 fan speed performance. This comes at the cost of slightly worse max speed CADR vs the venerable Arctic P14.
The Austin Air HealthMate is great as a noise machine. Very loud. It’s a HEPA filter and lasts 5 years. Never seen any other that lasts that long, but you pay for it upfront. after-market replacements are $250-300 for another 5 years.
I have that machine. It seems better at filtering chemicals and VOCs but not great at filtering particulates. It gets rid of odors very well but my PM2.5 meter barely budges.
I have IQAir HyperHEPA filters, plus whole-house AprilAire HEPA filters on the HVAC equipment in the attic. I’m fine on particulates.
Where I need extra help is with VOCs in certain locations. Like, in or near bathrooms. Or the cat litter boxes. IQAir does sell their GC line for that, and we have a couple of those. But the activated carbon filter media is super expensive. And these things are huge. Like, bigger than a dorm refrigerator.
this feels like a 'dose makes the poison' scenario. you're talking about maybe $10 of difference annually if both were run continuously. and that's only if you bought an inefficient air purifier - if you elected to use, for eg, four Arctic P14 PSTs in a CR box then that's maybe double the kWh. this ends up being a couple of bucks more annually for the added benefit of having better air quality
It just looks like fog, but it is smoke, and the sky has an unusual orange color. Smells and tastes like you are standing in the path of a campfire, but you can't move out of the way. It irritates your eyes and throat if you spend more than 20 mins out there. You can go inside, but if the building you are in is leaky, it will smell like smoke inside there too.
The actual fire was hundreds of miles away. You can try driving in any direction for hours and not be clear of the smoke. Still, compared to other areas, this is barely worth complaining about.
My allergies became generally better at all hours just from sleeping in super cleaned air.
Why? Reducing baseline inflammation perhapse? Maybe decreased inflammation during sleep helps too, improved breathing? idk. Whatever it is this organism seems to prefer it.
Even when exposed to allergens during the day the run up to sneezing is much slower or doesn't happen.
An air purifier is the best noise machine for me, much better than the white noise machines with the tinny speakers. Even the brown noise setting on those isn't nearly deep enough to let me sleep.
Yea, having it and using it at max just as I go to bed just makes me feel much better for the air I'll be breathing while sleeping. I also used to always fall asleep to some noise or music, so this is such a nice replacement
I have 4 Coway and 2 Winix purifiers and I can confirm: they're great sleep noise generators! The plastic front pieces and the filters themselves block/baffle any high frequency noise from the fans, leaving you with a pleasant low/mid frequency whooooooosh. I like it better than the sound from small cheap solid state machines; their small speakers can't do low frequencies.
Hmm. The word "most" is doing a lot of work here.Depends if you enjoy fresh air when you sleep or not. If you've ever monitored CO2 levels you know how quickly they climb in a closed room.
But, if you are blowing fresh air into a room, or have the windows open, the filtration effectiveness of these units approaches zero pretty rapidly. And these air purifiers aren't exactly free to run: they use ~50-100W of power and if you run them 24/7 you can expect to spend $100+ per year on filters.
So there's no perfect answer...
What are people's target AQIs? I have indoor monitors in our high-rise building in SF and live 100 m from the freeway and we have:
That's the baseline. When we're cooking, like now, it's: None of those seem particularly concerning. We have a gas range, and 15 min past the end of cooking everything is fine. I must imagine that most people don't live right next to the freeway so they probably have even better air quality except during wildfire season.CO2 - I'm thrilled with anything less than 800 ppm (half justified by being the lowest number I've ever seen a study suggest might have health effects, half justified by being at a point where I personally don't notice that I'm more drowsy).
PM2.5 - My impression is the health risks here are more cumulative exposure (and include things I'd like to go without in my life, like alzheimers) and a pretty straight line of "lower is better all the way to zero". The WHO's guideline is mean exposure of 5 µg/m³ so I guess I'd adopt that if I had to put a number on it. (But it's a mean, I wouldn't worry about briefly exceeding it)
PM10 - No real opinion (I'd rather worry about PM2.5)
VOC index - I'm not sure this is a standardized thing, but the version I've come across is an index relative to the average that particular sensor has seen in the last 24 hours. So there's no standard possible here.
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As for a gas range I would worry about NOX considering the studies with them causing and aggravating asthma. That said your CO2 levels are low so I suspect you might have sufficient ventilation that this isn't a huge issue for you (especially if that ventilation is in the form of a fume hood over your stove that you actually use).
An air purifier is a good addition to a kids bedroom.
I got one during Santa Cruz wildfires in 2020 and now the kids have a pavlovian reflex to sleep once that gets turned on.
Ikea makes an air-purifier table, which is a end-run around it being a useless box in the room when switched off.
It's fairly expensive, not as good as a purpose built one, but it blends into the average room pretty well.
This makes me wonder, for a truly travel-size solution (or just otherwise compact needs), if there's a viable alternative that directs filtered air at a sleeper's head? In other words, would the net effect be equivalent for one person (such that they're breathing more or less the same cleanness of air)?
I grasp that such an approach might draw unfiltered surrounding air along with the filtered stream of air, and imagine that it would likely be easily overwhelmed by a steady supply of exceptionally polluted air (wildfire smoke or simply a heavily polluted urban area), but I still would be interested in knowing if the compromise never overcomes a level of placebo effect, or if there's a point where it actually achieves measurable benefit (both in efficacy and portability—like a even more compact and directional version of the Corsi-Rosenthal computer fan solution.)
I have seen models designed this way! Vornado used to make one, I think it's discontinued.
These directed-air "personal models" make a lot of sense to me... at least in theory. I haven't seen them properly tested.
The big air purifiers work great.. if the room is closed up. But their effectiveness approaches zero if you have the windows open or otherwise have unfiltered air entering the room. Which is kind of important, if you don't enjoy breathing in sky high levels of CO2. (If one's allergies are bad enough, or a wildfire is raging outside, CO2 might of course be preferable to particulates)
I bought a large soldering iron air purifier and it turns out to be great; it has a continuious speed selector, easy to replace filters, and very pleasant spectrum. I like it better than the air conditioner, which cycles on and off noisily.
One of the best air purifiers you can get (linked in the above writeup) uses PC fans and a custom controller where you can control the speed/volume: https://housefresh.com/best-air-purifiers-we-tested/#2-best-...
Why is this so expensive? It's literally 4 PC fans and some plastic trays? I presume you bring your own filters.
Filters are included, as well as high quality fans, AC/DC converter and speed controller, and the portable/collapsible enclosure. It's really not that expensive vs trying to put together the parts yourself, and it's tested to work very well compared to other more expensive filters.
Those fans will not have sufficient static pressure to be useful. These makeshift purifiers may be great in a pinch (wildfire season and stores are all out), but far from the best.
This is indeed the "conventional wisdom," but if you do the math it turns out this is incorrect.
The trick is to use high-airflow MERV 13 filters (ideally 3M 1900, which has high pleat count and low resistance) instead of high-resistance HEPA filters, so axial PC fans can generate enough pressure.
At that point, you’re not doing any actual air filtering. Just use them as fans instead.
Merv-13 means it filters at least 75% of the particles passing through it.
For a standalone air filter which is pushing the filtered air into the same room its drawing from, we can assume reasonably good mixing of the intake and exhaust air. Thus to be equivalent to a HEPA-filter it only needs 1/3rd more airflow... Which really isn't much.
This doesn't follow for a a fancier setup where you're taking dirty air and blowing it into a cleanroom or something... but that's not how we're typically using household air filters.
The linked PC-fan purifier has been tested and shown to purify air faster than the conventional alternatives, and are not makeshift, so I'm not sure what you are referring to.
From the specs it looks like they are probably closer to higher-static-pressure server fans, the CADR is a few hundred CFM and it pulls 30+ watts. And as with many of these designs, you can compensate for low pressure performance by increasing filter surface area... the greater the surface area the lower the pressure drop. Of course, the problem with this is you are just spending more money on filters, which is the expensive part.
The filter cost for the AirFanta 3 doesn't seem particularly high? In fact it seems cheaper than competitors.
All the purifier companies realized they make more money selling overpriced filters, so $60+ for the OEM filters is common nowadays. Despite it just being a standard HEPA filter cut to a specific size.
Airfanta 3 Pro filters (four) - $57
Coway Mighty Filter - $60
Coway Mighty2 Filter - $70-$80
I'd be concerned about the availability of filters after a few years. Some of these companies have been changing their models and filter type every year to add some nebulous feature. Others just go out of business.
Yeah, the retail prices of filters is all over the place because of the popularity of razor/blade model of pricing. I'm not talking about that, I'm talking about the BOM itself -- this device is using 4x the filter media of comparable filters, which would typically have one filter that size.
HEPA media itself is a commodity and aftermarket filters (and the BOM cost) tend to level out at whatever rate is minimally profitable per area of filter media.
The upfront cost of this device is high for what you get, because you're mostly buying filter media. The device itself is not much of a polished product. I'm sure it works fine but I wouldn't want one in my living room.
For cost over time, twice the filters means twice the replacement interval, so the additional filter cost cancels out.
You can use them as random number generators, to replace your lava lamp for example.
I'll stick with RFC 1149.5.
I use my philips as noise machine :P But like year ago it changed noise and I don't like it that much anymore
True, mine does that job really well too. Not too much high in it either, just a nice low rumble.
For sleeping I prefer rain sounds though
Does that mean your air doesn't get filtered if you stop or decide to turn down the white noise?
I prefer having quiet air filters that I can run all day (based on air quality) instead of noisy ones I only use at night.
For air filtering, you want big fans that move relatively slowly. At least, at lower settings.
I still haven’t seen anything else that can compare to IQAir HyperHEPA filters. They use these things in hospitals.
All my air filters are sized to clean air while being quiet.
Turning them up to med/high would just cause too much airflow.
If you turn it off, sure.
I have one in the bedroom. On low, I barely hear it during the day (extra ambient noise from outside) but at night the white-noise is subtle but effective. That said, I don't like "loud" white noise, just a quiet hum.
YSK on low you won't be getting much air cleaning power. All air purifiers are rated based on their top fan speed.
Housefresh, which is a criminally underrated review channel btw, recently did a comparison of PC fans for this purpose. The Thermalright TL-14C family came out strong in the "Silent" category, with the best ultra-quiet 24/7 fan speed performance. This comes at the cost of slightly worse max speed CADR vs the venerable Arctic P14.
https://www.youtube.com/watch?v=Rlz37IdCcIE
Many air purifiers are silent on lower settings and louder on higher settings. If I want noise I turn mine up. If I want less noise I turn it down.
The Austin Air HealthMate is great as a noise machine. Very loud. It’s a HEPA filter and lasts 5 years. Never seen any other that lasts that long, but you pay for it upfront. after-market replacements are $250-300 for another 5 years.
I have that machine. It seems better at filtering chemicals and VOCs but not great at filtering particulates. It gets rid of odors very well but my PM2.5 meter barely budges.
I have IQAir HyperHEPA filters, plus whole-house AprilAire HEPA filters on the HVAC equipment in the attic. I’m fine on particulates.
Where I need extra help is with VOCs in certain locations. Like, in or near bathrooms. Or the cat litter boxes. IQAir does sell their GC line for that, and we have a couple of those. But the activated carbon filter media is super expensive. And these things are huge. Like, bigger than a dorm refrigerator.
So, I welcome an alternative that does VOCs well.
Yeah, it's a completely different kind of air purifier than the "tape a HEPA filter to a fan" ones, which is why it costs $1,000 instead of $150.
Which PM2.5 meter do you have? I’ve been looking to buy one and AirThings keeps coming up.
I have a Temtop indoor air quality monitor. The exact model seems to have been discontinued but it can measure PM2.5 and formaldehyde.
Air purifier is gonna use a lot more energy than just a small speaker. The energy cost swamps everything long term
this feels like a 'dose makes the poison' scenario. you're talking about maybe $10 of difference annually if both were run continuously. and that's only if you bought an inefficient air purifier - if you elected to use, for eg, four Arctic P14 PSTs in a CR box then that's maybe double the kWh. this ends up being a couple of bucks more annually for the added benefit of having better air quality
I think $10 is too low an estimate.
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Alrighty, don't a lot of people already do this? Sometimes I'll do both an air purifier white noise and some music or something from myNoise
I prefer pink noise.
Glad to see I'm not the only person who does this
I've considered an air purifier for allergy reasons, but...
>removes smoke and infectious particles
Where do people live that they need to remove such things, 18th century London?
This is approximately what it looked like near my area in mid July for a few days.
https://commons.wikimedia.org/wiki/File:Wildfire_smoke_Wyand...
It just looks like fog, but it is smoke, and the sky has an unusual orange color. Smells and tastes like you are standing in the path of a campfire, but you can't move out of the way. It irritates your eyes and throat if you spend more than 20 mins out there. You can go inside, but if the building you are in is leaky, it will smell like smoke inside there too.
The actual fire was hundreds of miles away. You can try driving in any direction for hours and not be clear of the smoke. Still, compared to other areas, this is barely worth complaining about.
Anywhere in the US west of Texas and most of Canada.
Infectious particles? In most of USA and Canada? I don't believe you.
I'm talking about smoke, I don't even know what an "infectious particle" is.
Yes, there are viruses in USA & Canada.
I use mine just to purify air for my precious LTO tape drive. My baby doesnt like dust
Allergens are likely considered "infectious particles" for that particular sentence.
>Where do people live that they need to remove such things
SF Bay Area during the summer fires of a few years ago
Almost anywhere now in North America or Europe during the summer.
Doesn't even need to be during the summer.
Wind blows smoke around. There are currently fires in northern Michigan that are affecting the air quality in Chicago, which is 350+ miles away.
https://data.usatoday.com/fires/
As an allergy enjoyer there is no air too pure.
My allergies became generally better at all hours just from sleeping in super cleaned air.
Why? Reducing baseline inflammation perhapse? Maybe decreased inflammation during sleep helps too, improved breathing? idk. Whatever it is this organism seems to prefer it.
Even when exposed to allergens during the day the run up to sneezing is much slower or doesn't happen.
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Why?