Most Air Cleaning Devices Have Not Been Tested On People (theconversation.com) 54
A new review of nearly 700 studies on portable air cleaners found that over 90% of them were tested in empty spaces, not on people, leaving major gaps in evidence about whether these devices actually prevent infections or if they might even cause harm by releasing chemicals like ozone or formaldehyde. The Conversation reports: Many respiratory viruses, such as COVID-19 and influenza, can spread through indoor air. Technologies such as HEPA filters, ultraviolet light and special ventilation designs -- collectively known as engineering infection controls -- are intended to clean indoor air and prevent viruses and other disease-causing pathogens from spreading. Along with our colleagues across three academic institutions and two government science agencies, we identified and analyzed every research study evaluating the effectiveness of these technologies published from the 1920s through 2023 -- 672 of them in total.
These studies assessed performance in three main ways: Some measured whether the interventions reduced infections in people; others used animals such as guinea pigs or mice; and the rest took air samples to determine whether the devices reduced the number of small particles or microbes in the air. Only about 8% of the studies tested effectiveness on people, while over 90% tested the devices in unoccupied spaces.
We found substantial variation across different technologies. For example, 44 studies examined an air cleaning process called photocatalytic oxidation, which produces chemicals that kill microbes, but only one of those tested whether the technology prevented infections in people. Another 35 studies evaluated plasma-based technologies for killing microbes, and none involved human participants. We also found 43 studies on filters incorporating nanomaterials designed to both capture and kill microbes -- again, none included human testing.
These studies assessed performance in three main ways: Some measured whether the interventions reduced infections in people; others used animals such as guinea pigs or mice; and the rest took air samples to determine whether the devices reduced the number of small particles or microbes in the air. Only about 8% of the studies tested effectiveness on people, while over 90% tested the devices in unoccupied spaces.
We found substantial variation across different technologies. For example, 44 studies examined an air cleaning process called photocatalytic oxidation, which produces chemicals that kill microbes, but only one of those tested whether the technology prevented infections in people. Another 35 studies evaluated plasma-based technologies for killing microbes, and none involved human participants. We also found 43 studies on filters incorporating nanomaterials designed to both capture and kill microbes -- again, none included human testing.
Uh, OK. (Score:3, Insightful)
Re:Uh, OK. (Score:4, Funny)
Indeed. Why are animal tests necessary at all in places that have "allow something first, take care of the consequences later" type of consumer laws?
Just as you allow selling unverified shit, mandate full data collection, so that the consequences are immediately known.
And, of course, in this age of can-do-just-anything "AI", why even bother with tests? Run everything by the chat-gpt and call it done.
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Indeed. Why are animal tests necessary at all in places that have "allow something first, take care of the consequences later" type of consumer laws?
Just as you allow selling unverified shit, mandate full data collection, so that the consequences are immediately known.
And, of course, in this age of can-do-just-anything "AI", why even bother with tests? Run everything by the chat-gpt and call it done.
Pretty much this.
The Fine Summary mentioned "portable a so I assume we're talking about consumer units rather than commercial or industrial grade HEPA filters as part of a HVAC system.
As these units are essentially scams, like vitamin supplements, they're tested to the point where they know that they won't flagrantly break any obvious laws. They're not really tested to see if they work, in fact like vitamin supplements it's better if they don't work as it means the product can't be accidentally classi
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As these units are essentially scams
Of course.
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I bought my air purifiers to get dust and shit out of the air, not viruses. None of the marketing on the air purifiers said anything about viruses or infections, in my experience the vast majority of air purifiers (certainly all the reputable ones) make no medical claims. At most they'll talk about what percentage of what size of particles they'll remove from the air. So what part of them is a scam?
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I did say "all the reputable ones". I've never heard of "Iso-Aire", and none of their products are available for sale in any major retailer that I can find. Or any minor retailers either, from what I can tell.
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Ratings go from MERV 1 to MERV 16 and then HEPA, and the difference with each higher level is that it it will be able to catch a higher percentage of finer particles. For particles in the range of bacteria and viruses, a MERV 11 will only stop about 20%.
"What is a MERV rating" - https://www.epa.gov/indoor-air... [epa.gov]
3M, MERV 13, Particles Captured: Lint, Mold spores, Pollen, Smoke, Dust mite debris, Bacteria, Pet dander, Viruses, Dust, Smog Particles, Cough/Sneeze Debris, Candle Soot, Exhaust Particles - https:/ [3mcanada.ca]
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If you look at Iso-Aire's website, they're going way beyond the definition of MERV and claiming that their products were "developed to address COVID-19". Most air purifiers will just make a claim about capturing X% of particles of Y micron size.
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From the site:
"Considering the threat that the spread of COVID-19 and other germs pose, an upgrade of a building’s air filter to a HEPA is a far more effective step than just to a MERV 13 considering the small size of a virus (0.06-0.12 microns); the more efficient the filter is, the better." - https://www.iso-aire.com/blog/... [iso-aire.com]
Doesn't sound wrong. It seems to me they're saying a MERV 13 filter isn't good enough for viruses and are suggesting (HEPA) MERV 17 or higher.
> they're going way beyond the d
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I think they're going too far as soon as they're making medical claims without some sort of medical certification. And on their residential product page, they specifically say that their air purifiers were "Developed to address COVID-19", and in their FAQ, they say "The powerful ISO-Aire filtration system was purpose-built to address COVID-19 and other droplet and/or airborne-based infections in healthcare settings."
They repeatedly mention the CDC on their website, and in most places just word it along the
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The early advice about cleaners for COVID was wrong. It is interesting that all the complaints from the right about the CDC they seem to ignore this, the biggest mistake they made. It was believed that COVID would only survive in heavy water droplets and would infect a person by them touching a surface and then touching their eyes or mouth, this was also used as an argument against masks (masks would encourage touching around the mouth). It turns out COVID is inhaled and can't survive in a drop on a surface
Animal testing is not necessary (Score:3)
We could be testing on desperate college students.
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as your sig mentions a very smart stable genius, perhaps the testing can be done on undocumented immigrants.
"“I'm intelligent. Some people would say I'm very, very, very intelligent.” — President Donald J. Trump"
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This assumes that the testing is harmful. The test could be something like placing one in one of two offices and seeing if people in one suffer lower infection rates than the other. The alternative being the status quo, no protection and the yearly respiratory viruses do the rounds.
HEPA filters and UV lamps have been verified to kill viruses and bacteria, and HEPA also removes other harmful stuff like PM2.5. The question is if cycling air through a filter in a room is effective.
There has been some clinical
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It does no such thing. In fact, you are assuming exactly the opposite, that testing isn't harmful. Without testing, claiming harmful or not is just an assumption.
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There is no assumption. Say you test by installing an air purifier in one office and leaving one unpurified. You need them to be as similar as possible. You can then see how many people from each get the yearly respiratory viruses. Expand to multiple locations until it becomes statistically valid.
There are other non harmful methods. You can use particles with a strong odour that are the same size as viruses. If the test subjects can smell them, they were not filtered out. That's the standard test for mask f
So what? Overlapping studies are valid (Score:5, Informative)
I don't need to know if my air purifier improves my health. I only need to know if it reduces PM2.5 and PM10 particulate concentration in my house and if it does so without generating ozone. There are plenty of other studies on the effects of PM2.5, PM10, and Ozone on my body.
Next article: No studies actually exist to show if washing machines make people look cleaner, so far all the studies have been limited to cloths.
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Not just for your health, to reduce the amount of dust build up too.
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So much this. I've run two air purifiers in the attic which we've renovated this year. It's truly amazing how much airborne dust they can reduce in a dusty environment. Yes I've had to vacuum the filters out every week.
There was a week period where I forgot to turn it on, and I noticed an insane amount of building dust migrated down the stairs and into other rooms during that period.
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Yeah, that's a big one. Indoor air quality is often worse than outdoors for many reasons - including VOCs caused by offgassing of things. You buy a new couch, it's made with new materials and things like varnishes and waxes and coatings and that stuff off-gasses into the air. And your house generally doesn't have much air circulation - the whole point of the indoors is generally to keep the outdoors outside, so the stuff accumulates inside in a closed space.
And dust is composed of human dead skin cells that
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It's a shame that box fans are not widely available in Europe, or we could have nice cheap and effective air filtration.
The IKEA ones are actually decent, although not cheap. At least the filters are reasonably priced.
I was thinking about one of those positive air pressure things. Install it in the loft, filters and warms the incoming air, and creates positive pressure so that at least pollution from outside the house doesn't come in. I'm not really sure how effective they are though. How much of the dust i
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the Netherlands has installed CO2 sensors in every classroom with the explicit instructions that if they go off, the teacher must immediately open the outside windows..
Ha! Joke's on them, my classroom doesn't have outside windows. Further, the windows it does have, facing an interior hallway, can not be opened.
I did place two air filters in my classroom (yes, I had to pay for them myself), and since I did, I haven't had allergy issues. My principal said absolutely no to the box fan DIY style, though.
Is this just sewing doubt in Science once again? (Score:2, Insightful)
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It's not *just* bullshit. They really should test to see how much effect they have. (I was surprised hat HEPA filters let so much through. IMNSHO it's not a strong enough standard. Of course, I'm more worried about pollen, I doubt that an air filter could reasonably be fine enough to remove viruses. That's more a job for UV. [Look up the origin of the term "filterable virus".])
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There may BE HEPA filters that go down to the micrometer range, but that sure wasn't true of the ones I bought. It needs to be a stronger standard.
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There are lots of machines that can use HEPA filters but aren't airtight themselves. If you truly want HEPA filtering then you need a machine which has all it's seams sealed. The real ones are expensive.
Re: Is this just sewing doubt in Science once agai (Score:3)
How much gets through a HEPA filter is useless information without also knowing how much air goes through per minute. HEPA filters by definition are supposed to catch 99.97% of particles in the hardest size category of particles to catch, 0.3 microns, (Smaller particles are easier to catch.) but on two passes, it catches much more, on three passes even more etc.
So HEPA may not even be the optimal filter grade for room air cleaning. I read some IAQ nerds think MERV-13 filters and more fans is better.
For air
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Displaying Ignorance (Score:2)
As for infections, reducing the number of bacteria and viruses is clearly good and the more you reduce it the better. However, translating that into
Hmm... unfortunately we need to vet this further (Score:1, Troll)
Just doing a quick run-through on all the authors - the vast majority have exactly ONE paper published on that site (which is this current paper). I want to check whether or not that's common, but that will take some time.
Additionally, a bunch of them work for CDC - so unfortunately we also need to ask... are these all CDC "professionals" recently appointed by RFK, or are they actual smart medical people with a track record at the Center?
Maybe this is all actual great research being done by great people...
Where's my cheese? (Score:5, Interesting)
Im reminded of a management book that went into how easy it is for employees, from the lowest level trainee all the way to the CEO, to lose track of a business's primary purpose, to make money.
Things like a chicken chain making wasted chicken the biggest factor in evaluating individual store management - so they'd stop making chicken an hour before close unless actually for an order, driving away customers and costing substantial profit.
Or filling up warehouses with parts that would take a decade to sell because that was the 'efficient' run length for that part.
Etc...
A study to determine that air filters actually improve health, and how much, would be good. Maybe it is mostly placebo, maybe for some strange reason it is harmful. Looking into it shouldn't hurt.
Logic says that fewer viral particles, fewer other particles, should help, but we have been surprised before.
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Logic, and vast studies over tens of Millions of people says that MRNA vaccines are safe, however, many, many very stupid people think they are NOT because they think that if they see a tictok video saying otherwise, and that they are on the same level of expertise as a person who went full time in College for 8 years, and did a dissertation on it.
There is so much stupid going
Re: Where's my cheese? (Score:2)
Yes, but 8 percent were tested with people.
Once you established that it works, you don't need to use humans for each test. Maybe a follow up note and then, but not every test. To do so would be cost prohibitive, and/or you would test less.
Let's be smart and efficient.
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"... a business's primary purpose [is] to make money.
That's like saying a person's primary purpose is to eat food. They need to eat food, they'll die if they eat food, but what happens to a person that sacrifices all else they do so they can eat more food, eat food faster, eat as much food as they can? C'mon.
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die if the don't* eat food.
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die if they* don't eat food
Maybe I'll die if I don't make typos.
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Well, yes, it is a rather obvious answer, but consider the number of examples where managers, supervisors, and employees lost track of the core reason they were being employed, how incentives could be messed up, and more, leading to loss of profit. It is easy to lose track of the core purpose.
Even my statement about being for profit is incomplete, because it needs to be profit in line with capital investment. If one could make more money just investing in the stock market, for example, why not do that ins
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"consider the number of examples where managers, supervisors, and employees lost track of the core reason they were being employed..."
I do! and I recognize it doesn't have to be this way. Just as I can consider how many people in my culture overeat, and I recognize it doesn't have to be this way. And just because I'm surrounded by obese people, who will tell me earnestly and sincerely and at length how good it feels to eat food and how painful it is not to eat food, this does not excuse overeating nor
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The problem with calling the writer 'that I quoted' irresponsible is that I didn't actually quote them. You're rushing to a conclusion on the basis of a couple half remembered aspects that the gp reminded me of.
As a matter of fact, said book emphasized:
Long term profitability vs short term.
Development of human resources - lots of examples of where they fired 'expensive' but highly skilled workers to try to go cheap and it killed them. Basically, cheaping out on your product can result in lost sales and lo
But have them been tested on air? (Score:4, Funny)
Also, I am pretty sure that most people won't easily get through an air filter, even if finely chopped.
So..what do they propose ? (Score:2)
Ethical problems with testing on people (Score:3)
There are ethical problems with testing on people; Generally you only want to test some new thing against the current standard of care, because it would be a dick move to not do anything or provide placebo treatment and leave the test subject to suffer.
That said, it's 100% fine to test air cleaning devices with just air testing. Their job is to clean the air, after all. If the mechanism of disease spread is through the air, and you can demonstrate that airborne disease is decreased through use of your device, then it's a very small, logical, and reasonable step to claim that your device helps reduce the spread of disease.
You do not need to take healthy people, put them in a room full of disease, and see how many get sick with or without your air cleaner device. That's not how this works.
But that's not to say testing "on people" is impossible. For example, ultraviolet germicidal irradiation [nih.gov] has been subjected to multiple randomized, controlled, double-blind trials and is absolutely effective at safely reducing disease spread when applied properly.
=Smidge=
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It's not 100% fine to just test the air for what you're trying to filter. That's the whole point of the article. There's new filtering tech being used which may be producing toxic by-products. If you only test the air for dust you won't know if your product is giving off toxic fumes. And probably that's the point of not testing for it.
We're talking about burning anything in the air with plasma or forcing air through nanoparticle frameworks. We're not talking about basic 'cloth' filters.
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> It's not 100% fine to just test the air for what you're trying to filter. That's the whole point of the article
No, it's not. The "Whole point" of the article is "We don't know if reducing the number of airborne contaminants actually reduces rates of infection."
Indoor air quality is broadly measured, including the types of things these researchers complain about. Ozone and formaldehyde? TIGHTLY regulated in commercial and industrial standards.
It's pure FUD.
=Smidge=
Tested on People? (Score:2)
I would hope that most air cleaning devices filter out people. They're much larger than e.g. a dust particle.
This just in (Score:2)
Automotive crash tests were performed using dummies, and not real people. This throws into question the validity of all the safety tests currently performed on automobiles in the United States.
You simply must test on humans or your results will rightfully be called into question.
Do we really need that? (Score:2)
I mean, most of these air filters say right on them the size of the least minuscule particle they'll pass through, generally not significantly more than 10 microns. People are way bigger than that, so I'm pretty sure 99.999% of the filters on the market today will not have a problem filtering humans out of the air.
Simple solution: Don't make health claims (Score:2)
Sure, go ahead and test effectiveness of improving health in humans. That's good to know. But, I don't think I've ever bought an air filter because I thought it would improve my health. I always had a more immediate goal: Remove an odor, make it easier to breath by removing smoke (blame Canada!), alleviate pollen allergies. These things are all primary effects that the user will be able to judge within hours or days of installing the filter.
Measuring health benefits is tricky. Studies take a long time,
What about airplanes? (Score:2)
Airplanes filter a lot of air through HEPA filters, and have done so for years.
Millions of people have spent long periods of time breathing it, in particular the crews.
You could say the same for surgeons (ORs are heavily filtered, cold and high pressure).
I mean, there's a large population that uses those a lot, and it's probably fairly easy to find people who haven't been exposed to much HEPA filtered air.
It shouldn't be super hard to do an observational study.
So ... (Score:2)