Air Purifiers

Which would be valid medical expenses, and what documentation would be needed?:
-Advanced air filtration system (particulates, chemicals, hepa and activated carbon filtration) for allergies & chemical sensitivities
-Vacuum with hepa filter (a far shot, but worth asking)
-Home water filtration systems, shower dechlorinator and tap purifier.

I live in an extraordinarily polluted environment, and right now, the cost of breaking my lease and problems associated w/ relocating now would exceed the cost of this very expensive air purifier.
http://www.airpurifiers.com/products/iqair/gc-chemisorber.htm
If it works, it’s worth the money (esp. since I have chem sensitivities & allergies, so I’d probably find use for it anywhere), but if it doesn’t, it’s a huge waste for a glorified hepa filter (which is what it’d amount to if the chemical filtration didn’t work).
So my question is, how exactly does it filter out
Sulfur dioxide
Formaldehyde
Carbon dioxide
etc.
I’d be particularly interested to know how it can seriously filter Carbon dioxide, since that’s so prevalent in the air, I’d think that any filter for it’d be worn out within a day. That one in particular makes me question the validity of the product.
The sulfur dioxide, formaldehyde, and particulates from deisel are all very important to me, since these are some of the worst problems in this place, wedged between a factory w/ high sulfur dioxide emissions and an expressway, in a building full of gas stoves and heat, aside from fireplace smoke wafting in from the neighbors on some days.
Can someone with some knowledge of how these advanced air purifiers work please explain this to me? Would I be throwing my money away? (Please note that this is not a small purchase for me, especially looking at the cost and frequency of replacing the filters)

No central air or heat, so in winter windows are cracked and in summer windows are screened but opened. I bought the air purifier to help with allergies and after 2 nights it does seem to help, but think I need to go back and get the larger one. This one is for room 10 x 12 and my room is 16 x 13 and is connected to kitchen with no dividing door. Am I fighting a losing battle, or will this unit help pretty bad allergies (I think mostly to dust)? Would love to hear your experiences.
P.S. I bought the Holmes brand with Hepa type filter.
Thank you.

Are air purifiers really good in cleaning the air? Are the ones that don’t need filter replacement the better ones? I have allergies and heard they are quiet good.

I moved into an older house in October and since then, my allergies have been really bad. I was looking into the Rabbit Air purifier but it’s a lot of money to spend without first getting people’s opinions.

Does anyone have personal experience using one? Did you notice a difference? Are they a scam?

i have allergies to dust and mold and bought an air purifier. i’m not sure if i am supposed to close my windows and doors when i use it. i am also not sure if i should always leave the house fan on to circulate air (or how often to use it). does anybody know how to circulate air and use an air purifier? (another question is how long to run the ionizer on the purifier or if i leave it on will the ozone be bad for me).

I have very bad sinu and allergies. Which one would be better to buy to put on while I sleep.

I suffer major allergies from dust, pollen, mold and pets. I want an all-around purifier that helps with these and gas and chemicals.

I have done EXTENSIVE research and YES I know IQ Air is best but it’s rather large and expensive. Blue Air and Austin Air are highly rated as well, but they’re rather large for my bedroom. I have been looking into the Sharp Plasmacuster (not the model with the annoying upkeep of the humidifier) and Rabbit Air as well, which are more stylish and a tad cheaper. Anyone with experience with any of these or suggestions?

I live in an apartment in the middle of the city. My room gets dusty really easily and I have to dust everyday. I don’t have any allergies or asthma problems. My question is, is it worth investing in a good air purifier ( e.g.> 0, HEPA filtration etc, or is it good enough to buy a cheaper air purifier(0) with no HEPA filtration, just for the sake of keeping my room dust-free?

We live in a cozy suburban home with two domestic short hair cats, and two dogs,(a teacup chihuahua and a beagle/hound mix). The cats are strictly indoors and the dogs only go outside to potty and for walks. We keep all of our pets clean and they are all well taken care of but the shedding and pet dander are becoming a concern of mine because they are irritating my allergies a little. We regularly vacuum but seeing as it’s too cold outside to leave the windows open to help keep the house aired out I was wondering the best way to keep the air in the house and everything in it fresh from pet dander and odors. Are there any sprays or cleaners? And would an air purifier or something like that help?