Air purifiers: do they work?

[Chemist]

Is there a lack of air turnover in your basement?  I read an article in Consumer Reports (I believe) that warned against air ionizing purifiers due to generation of ozone.  Some HEPA type filters also have ionization built in. 

I have owned a few large HEPA type filters, mostly from Sears.  Some were loud so that is something to consider.  It sounds like you would need not just a HEPA filter but also one that has a decent carbon filter.  I used my filters with birds which mostly generated dust but for litter box odors you would probably need carbon type filtration. 

[Chemist]

Oh, in the end I decided it wasn't worth the money for replacement filters etc. for the little difference it made for me.  If you consider buying one make sure to check prices on replacement filters (and make sure they are easy to find). 

[margomaps]

Is there a lack of air turnover in your basement?

Yeah, pretty much.  The only sources of ventilation are the basement stairs, a single half-height window which is rarely opened, and the bulkhead exit which never gets opened.  So I imagine part of the problem is that the stinky cat-box air just keeps accumulating.  I do notice that when I open a window and put a fan in it (facing out), it does smell a lot better down there.

[ByronB]

Our catbox makes the whole basement smell like...well, a catbox.  I'd really like to find a solution that doesn't involve getting rid of the cats.    It doesn't matter if we clean the catbox twice a day, it still makes the basement smell a little bad.

I was wondering if anyone has had any luck with air purifiers?  I see them all the time at buy.com (and elsewhere).  They claim to remove various odors and airborne particulates, but I'd like to know how well they might work at making my basement smell less like a catbox.  Here are a bunch at buy.com:  http://www.buy.com/retail/usersearchresults.asp?querytype=home&qu=air+purifier

Prices vary from < $25 to hundreds of dollars.

Any thoughts?

Ideally you would spend $8000 on a new high-efficiency furnace with some supply air and return air in your basement (don't put any returns in your basement if you have non-sealed combustion chambers though, the technically it could cause CO poisoning then) and put a UV lamp above the furnace to kill off any bad odors and if you get something like a Carrier Infinity (http://www.residential.carrier.com/systems/infinity.shtml) you can very cheaply run the fan on low speed to circulate air throughout the house keeping smells out and the whole house an even temperature, very nice system, I've installed about 10 of them and everyone really liked it... I'll assume that is not an option though, just go for something with a UV light, a filter, and a fan; that should do the trick (I'd keep away from anything that produces ozone though because it is a toxin and has recently been shown to reduce lifespan).

[MaineShark]

Ideally you would spend $8000 on a new high-efficiency furnace with some supply air and return air in your basement (don't put any returns in your basement if you have non-sealed combustion chambers though, the technically it could cause CO poisoning then) and put a UV lamp above the furnace to kill off any bad odors...

UV "stick" lamps (if that's what you're suggesting) are object cleaners (eg, for A/C coils, to prevent mold growth) and won't actually have any appreciable effect on moving air.

For a lot less than $8k, a full-on standalone HEPA system with UV purification could be added, last time I checked prices.  That would be on the order of the filtration level used by a cleanroom...

Joe

[Lloyd Danforth]

Is there any way that you could put the box near a window that you could mount a small exhaust fan in?  You could have dryer vent hose going too it from the cat box.  I'm guessing that there is a device out there that will power the fan on and off in intervals.

[MaineShark]

Is there any way that you could put the box near a window that you could mount a small exhaust fan in?  You could have dryer vent hose going too it from the cat box.  I'm guessing that there is a device out there that will power the fan on and off in intervals.

Yeah, that would be pretty simple to do with a ventilation control.

Of course, ventilation comes at the cost of pulling in cold air during the winter, and hot air during the summer, so I'd recommend a heat-recovery ventilator (great for replacing bathroom exhaust fans, too).  That way, most of the heat from the outgoing air is transferred to the incoming air.

Joe

[ByronB]

UV "stick" lamps (if that's what you're suggesting) are object cleaners (eg, for A/C coils, to prevent mold growth) and won't actually have any appreciable effect on moving air.

On the contrary, UV is about the only way to purify (not filter, but actually break apart harmful molecules) without using ozone, just I would recommend a bulb that filters out the 185 nm range, as 185 nm is known for producing ozone. There are many UV lights out there designed to be mounted in the ductwork above the AC coil usually, but they are NOT for the AC coil it's self, in fact the UV lamp should have a shield to prevent the UV light from damaging the plastics used on the pan of nearly all new coils.

[MaineShark]

UV "stick" lamps (if that's what you're suggesting) are object cleaners (eg, for A/C coils, to prevent mold growth) and won't actually have any appreciable effect on moving air.

On the contrary, UV is about the only way to purify (not filter, but actually break apart harmful molecules) without using ozone, just I would recommend a bulb that filters out the 185 nm range, as 185 nm is known for producing ozone. There are many UV lights out there designed to be mounted in the ductwork above the AC coil usually, but they are NOT for the AC coil it's self, in fact the UV lamp should have a shield to prevent the UV light from damaging the plastics used on the pan of nearly all new coils.

UV, yes.  Stick lamps, no.  A stick lamp does nothing measurable to purify the air.  The intensity of UV from a lamp like that is so low once you go more than an inch of two from the lamp, that it does nothing - the air is moving by too fast.  To purify the air, you need to increase the dwell time by slowing the air, and increase the light intensity by using a concentrating reflector.

The stick lamps are just for treating coils (coils, not drain pans).  They do not treat the air.  Feel free to research the subject - the only systems that actually purify the air are systems with concentrators, and systems with (ozone-producing) catalysts.  As you said, the ozone-generators should be avoided, so that leaves the concentrating systems.

Joe