Which air sterilisers/purifiers work?

April 5, 2008 1:02 AM

Do you use an air steriliser or purifier? Does it work? Tell me about it please.

I've just moved house and it has become very clear that the previous occupants actually never cleaned the place. At all. (I found a bus ticket from 1951 in the skirting board!) There's dust and grime everywhere, and as much as I've been scrubbing away, it's an old house so I know more is lurking in the exposed floorboards, the old furniture etc, and when I wake up, I find I have a really bad sinus headache and a sore throat. The air is always full of dust and it settles everywhere.

So I'm thinking of getting an air purifier. These AirFree sterilisers caught my attention because they have no fan or filter - so are presumably quiet and easy to maintain. But they're pricey. Can anyone offer personal experience with these, or recommendations with purifiers in general? I've heard HEPA purifiers are good, but are they noisy? And if you live in London like me, where did you get yours?

posted by rose selavy to home & garden (12 comments total)

I can recommend that you don't get one that produces ozone - we had one for a while but it made me so nauseous we gave up on it.
posted by goo at 2:45 AM on April 5

For dealing with this sort of really serious dust problem, I suggest the quick and dirty solution: Get bare air-conditioner filter material (which you'll probably find is a 3M product; call your local air-con/central-heating place and ask) and just tape it onto the frame of a big cheap box fan.

That'll suck through orders of magnitude more air per minute than any small affordable air filter; it probably won't do a great job on smells or cigarette smoke, but it'll eat dust like nobody's business, and it's easy to replace the filter material when it gets clogged.

(You may be able to rinse the filters or hang 'em on a clothes line and beat 'em like a carpet; I don't know. I think you should probably just regard them as disposable items.)

If the building is full of materials that're constantly generating more particulates then you obviously need to address the problem at the source. But a big-ass filtered fan ought to give you some breathing space in the meantime.
posted by dansdata at 2:50 AM on April 5 [2 favorites]

If you have central air/heat, many manufacturers make pretty amazing "indoor air quality products."

Anyway, one such manufacturer, Carrier I think, has a filter/purifier that apparently not only captures all the dust and gunk, it also fries with an electrico-static shock the live viruses and what-not. I seem to remember reading that a similar system protects the Pentagon HVAC system.
posted by thomsplace at 3:25 AM on April 5

I don't smoke, but a relative does. His wife has a machine very similar to this one. Apparently, when she uses it, there is a very big difference in the amount of visible smoke and smell in the room where her husband smokes.

I have one of these, which I find really removes the smell of dog from a room. It runs 24/7, and needs cleaning out once every month or so. It makes about the same amount of noise as my PC does - hardly noticeable, and only then when I'm listening for it.

With regard to the products you mention, I can't find any indication of how they actually work. If it's a stream of warm air, then I have to question how effective they're going to be at cleaning the air 3 feet away, for example. A fan might be noisier, but it seems to me that it's going to drag more air through to be filtered. It probably does the job with regards to killing spores and such, but I think that's probably assuming that the room is sealed up. Any time you open a door or a window, you're going to get more contaminants back in again.

Also, I ask this completely without snark, but have you tried opening all the windows to get some airflow through?
posted by Solomon at 3:42 AM on April 5

it may be worthwhile to hire a professional cleaning service with hepa vacuums, like the ones they had to use on the apartments in downtown new york after 9/11. it'll cost, but it may be worth it in the long run.
posted by thinkingwoman at 5:01 AM on April 5

I've got some serious environmental allergies to dust. I bought a portable HEPA filter for my room and it's made all the difference between being able to breathe or not. There's been noticeably less dust on the furniture and in the vacuum when I've been cleaning, ... well, with the exception of when I vacuum off the filter surface. ;)
posted by SpecialK at 5:06 AM on April 5

Yeah, we keep 2 bunnies in the bedroom and their dander started to bother my wife quite a bit...we grabbed an ionizing air filter and if we forget to leave it on over night, she definitely knows it when she wakes up. It makes a huge difference in terms of air quality.

Definitely grab one of the filterless ones- they cost more upfront, but the filter replacements are expensive and will cost you a lot more in the long run.
posted by baphomet at 8:00 AM on April 5

I use Honeywell air purifiers. They have a replaceable carbon-black filter that deodorizes and catches large globby stuff, wrapped around a lifetime HEPA filter. They really do work, they deodorize and clean an entire room. Unfortunately, they're really expensive for what is basically a glorified air pump.

No idea where you could get them in London.
posted by ikkyu2 at 10:07 AM on April 5

Personally, I'd get it professionally cleaned. And if you have carpets etc. it might be a good idea to take them up and or get rid of any dirty furniture. I like in an old London house with centuries of dust in the cellar, between the floors, in the walls etc.) but we have mostly bare floorboards and not much in the way of soft furnishings and no real dust problem.
posted by rhymer at 11:05 AM on April 5

Go HEPA.

I kept a clean room once for some mushroom cloning work. Medical / Lab quality were too expensive, and the small drugstore purifiers did nothing to prevent contamination.

I built a bigger version of this DIY HEPA filter for less than $30, and never had airborne contamination again. I installed it inside cardboard box, and could add satchels of activated charcoal for odor issues or water absorbing polymer pellets to deal with humidity.

The most important line in the article is: The difference in the quality of your air will depend upon how much air you move through that filter. The small filter you link to does not look like it can pull that much air.
posted by Dr. Curare at 1:00 PM on April 5

Anything other than a HEPA mechanical filter or a two stage electrostatic precipitator will not be effective in removing household dust.

The purifiers linked to will not remove contaminants from the air, they will just chemically alter them with heat. That would be very useful to kill viruses, bacterial spores and mold spores but no at all useful to remove household dust.

HEPA units can be had for less than the price of the linked to filters, two stage ESPs on the other hand, are very pricey.
posted by 517 at 4:52 PM on April 5

I own an AirFree and frankly, you're right, it's a lot of money to spend on an unknown product. Although I notice some benefit from it being in the room (I'd sneeze a lot while sitting in the room, and after nearly a year of running it in there I rarely if ever sneeze anymore whilst in the room), I can't say that it's claims of things like "less mold" are really that noticeable but I can see that it does work that way in some fashion.

It is also not an easy thing to place in a room. it has hot air rising out of the top of it (think convection, not blowing) and always has a bright glowing blue light (I had a houseguest who is sensitive to ambient nighttime light and there was a lot of negotiation on what to do, as AirFree says to *never* unplug the steriliser). The hot air means you can't put it anywhere near drapes or furniture, and care must be taken not to have anything fall over it (this winter i nearly had my coat draping over it but caught it in time!)

My suggestion would be to stick with the recommendations of finding a HEPA filter that moves a large volume of air. You may have more noticeable results and feel better about money spent.
posted by kuppajava at 8:47 AM on April 6