Choosing an Air Purifier

Because we live on a tight budget, my roommate and I endured years of chronic scratchy throats and swollen sinuses before we considered buying an air-purifying machine.

We had identified the culprits: feathers and dander from our four free-flying pet birds; the fine city soot that blew in the windows; and musty cigarette smoke, followed by clouds of sickly sweet perfume, that seeped up through our floorboards from the apartment downstairs.

We imagined that our lungs had taken on the charred tint of a smoker’s, especially after September 11, when the acrid fumes from the burning World Trade Center periodically filled our apartment. By the end of last autumn, we were desperate for a breath of clean air.

Although air purifiers don’t generally absorb gases, such as perfume and cigarette odors, good ones will remove tiny airborne particles of dust, dander, tobacco smoke, soot, mold and pollen.

For guidance, we turned to a February 2002 rating by Consumer Reports (see box). Because our apartment has no central air, we chose a portable room air cleaner, the Friedrich C-90A, which CR rated most effective. Although it was also more expensive than models with high-efficiency particulate air (HEPA) filters, its washable filter would offset the waste and cost of replacement filters (up to $170 a year). And because it was designed to cover an area much larger than our 154-sq.-ft. room, it could clean on its lowest setting, which is the quietest and uses the least electricity. The machine circulates the air so quickly it creates a draft, which helps blow perfume and smoke out the windows, left open a crack.

In the course of our research, we learned to steer clear of ozone-generating air purifiers. While manufacturers claim that they cleanse the air of pollutants and bacteria, these machines actually may elevate indoor ozone to levels above federal health limits. “Avoid using air purifiers that produce ozone, which has consistently been shown to trigger asthma,” advises Luz Claudio, Ph.D., associate professor of environmental medicine at the Mount Sinai School of Medicine, in New York City. Are we breathing easier? So far, so good. When we checked the filter after its first day of use, it contained a thick, grimy layer of dust and feathers—a reassuring sight.


For retrofitting homes with central air, CR advises that homeowners first try replacing the existing filter with a pleated electrostatic one, inexpensive and easy to install yourself. If that doesn’t help, CR recommends the electronic precipitator models, which collect particles on electrically charged plates.

Aprilaire 5000 $500 Collector plates
Carrier AIRA $500 Collector plates
3M Filtrete Ultra Allergen Reduction 1250 $15 Pleated
Portable Room Air Cleaners
A fan draws air through, and particles are trapped in either a HEPA filter or on collector plates. These three can filter an area about 500 sq. ft.

Friedrich C-90A $475 Collector plates
Whirlpool AP45030HO $250 HEPA filter
Bionaire BAP-1300 $220 HEPA filter

This article was reprinted from “The Green Guide” newsletter, a publication of The Green Guide Institute. Since 1994, “The Green Guide” has been a premier consumer source for practical everyday actions benefiting environmental and personal health. Want more practical solutions that benefit the environment and personal health? Subscribe online to The Green Guide”.

Reprinted by permission of The Green Guide Institute.
By Allison Sloan, The Green Guide newsletter, May/June 2002.


Erika M.
Erika M3 years ago


.3 years ago

I am an air purifier geek and this is the best air purifier I've ever had

Thomas Glover
Past Member 5 years ago

Indoor air quality is much worse than the outdoors.TO clean dust allergens odors, and other airborne contaminants is very important to us. I advise you consider to have an to help you maintain a better indoor air situation I recently began having respiratory problems and allergies.I have a honeywell air purifier in my living room and it works well. by the way the
way, I think the testing questionaire is too complicated, it is too professional and not very practical,

Storeeverything N.

I like it! I like it a lot. You know exactly what youre talking about, exactly where other people are coming from on this issue. Im glad that I had the fortune to stumble across your blog. Its definitely an important issue that not enough people are talking about and Im glad that I got the chance to see all the angles. Outdoor Neon Signs

Tilak Ahuja
Tilak Ahuja8 years ago

It is interesting information. Due to the back draft pumping carbon monoxide and radon throughout your ventilation system, Energy Star says that it's essential to cover the filter slot after replacing the filter. The size of Filter for furnace should be an accurate size too. There's a brand new product called Filter Lock that's easy to use and saves energy.

Yo We
Yo We8 years ago

Air purifier reviews and HEPA filters

William P.
Past Member 9 years ago

Great tips on choosing an indoor air purifier. I have allergies, as does my oldest son, and the pollution inside my home really concerns me.
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Amy Hua
Amy Hua9 years ago

Thank you for the helpful article. I definitely need an air purifier and it's good to know of the different options.

Jacob Herrmann
Jacob Herrmann9 years ago

“Avoid using air purifiers that produce ozone, which has consistently been shown to trigger asthma,” advises Luz Claudio, Ph.D., associate professor of environmental medicine at the Mount Sinai School of Medicine, in New York City.

Mr.Luz Claudio,

Ozone is perfectly safe in low controlled levels.Our units are placed in the 911 Museum in New York City and in The Pentagon after the tragic events of 9/11

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