HEPA Air Purifiers

HEPA air purifiers: Proven technology

ConsumerReports.org tests a wide range of HEPA air cleaners, which start at about $250 for midsize units. Although it's easy to spend upward of $700 on a home air purifier, most users probably don't need the kind of high-level, multi-filtered performance these high-end models provide.

Because they don't rely on electrostatic or ionizing technology, manufacturers say none of the air purifiers discussed in this section emits any ozone (see the Air Purifiers and Ozone section for more information). Rather, HEPA purifiers simply use a fan to pull air through a filter.

Air-Purifier-Power.com and AllergyBuyersClub.com rate the IQAir HealthPro Plus (*Est. $900) as the best purifier on the market if you have severe allergies. It's one of the few home air purifiers that can capture particles down to 0.003 microns -- 100 times smaller than a normal HEPA filter. This means it can filter the usual allergens that most HEPA filters do (dust, pet dander, pollen and mold spores), plus tiny viruses and bacteria, combustion particles from smoke and automobile exhaust, volatile organic compounds (VOCs) and other chemical fumes, and cooking odors.

The IQAir HealthPro Plus air purifier can clean up to a 900-square-foot room. It uses a HyperHEPA filter (*Est. $190 for replacement filters), which has a filter-change alert and is easy to change every two to four years. Prefilters (*Est. $60 replacement cost) should be replaced every six to 18 months. The HealthPro Plus's gas and odor filter (*Est. $90 for a replacement filter) should be changed every year or two.

IQAir boasts a long list of hospitals and other medical facilities that use its purifiers. Newsweek's Peter Suciu tests the IQAir HealthPro Plus in "a basement that had been collecting dust for 20 years, and after two days, that musty smell was gone." Users at Amazon.com give this air purifier an average rating of 4 stars out of 5, with about 30 reviews posted at the time of our visit. Several users say the IQAir HealthPro Plus has noticeably helped their asthma and allergies, reducing the amount of medication they need to take, as well as cutting dust and odors in their homes. However, users also note that the unit is big, heavy and noisy when used on its highest settings, and the unit itself and its replacement filters are expensive. Some complain that it emitted a noxious odor.

Gregory Han of ApartmentTherapy.com tests the IQAir HealthPro Plus in his Los Angeles apartment and finds it dramatically reduces the particulate count in the air, especially when compared with cheaper purifiers from Holmes and Honeywell. "As impressive as all those figures are, what really struck me personally is the notable effect it had on my allergy prone girlfriend," Han says.

IQAir also makes the less expensive HealthPro (*Est. $750) air purifier. The only difference between the HealthPro and HealthPro Plus is that the HealthPro does not include the gas-and-odor filter, although you can add that later as an accessory. The HealthPro is rated for up to 1,000 square feet.

If you have a severe medical condition, then you should take a closer look at the IQAir HealthPro series. But for most allergy and asthma sufferers, a high quality, midpriced HEPA air purifier fits the bill. HEPA filters can remove 99.97 percent of particles larger than 0.3 microns, enough to help improve indoor air quality and reduce exposure to the most common irritants and allergens.

Among less expensive HEPA air purifiers, the Austin Air HealthMate (*Est. $490) earns a spot on Air-Purifier-Power.com's top-10 list and a very good rating at AllergyBuyersClub.com. "You would need to go about $500 higher, to the finest home air filters (found in IQAirs) to get better air purification," writes Ed Sherbenou at Air-Purifier-Power.com. Experts at AllergyBuyersClub.com say they particularly like its high efficiency/low maintenance combination. The Austin Air HealthMate filters collect not only dust, pet dander, pollen and mold spores, but the company says the unit also captures 95 percent of the smaller particles that pass through it, including chemical fumes, odors, bacteria and viruses down to 0.1 micron (not as small as the IQAir HealthPro Plus, but better than most HEPA filters). Its all-in-one HEPA/carbon filter pack (*Est. $195) needs to be changed only every three to five years, and ongoing costs are also lower than with the IQAir models.

The Austin Air HealthMate gets a high rating at Amazon.com, averaging 4 stars out of 5 with more than two dozen users posting reviews . Users say the unit seems to clean the air well, and they like that the filter lasts a long time. However, the Austin Air HealthMate is noisier than some air purifiers. Although AllergyBuyersClub.com says the lowest setting is quiet enough for sleeping, Air-Purifier-Power.com disagrees, saying that -- at 50 decibels -- it's too loud. Fifty decibels is about as loud as quiet conversation.

Although Austin Air doesn't make any claims about how large a room its filters can handle, several review and retail websites say the HealthMate can handle a room up to 1,500 square feet. They say the Austin Air HealthMate Jr. (*Est. $340), a smaller, less expensive version, can handle up to 700 square feet. But experts say those numbers are optimistic: AllergyBuyersClub.com says 650 square feet for the HealthMate is more like it, and 225 square feet for the HealthMate Jr. Air-Purifier-Power.com says the HealthMate will work best in a room no bigger than 200 square feet, or 110 square feet for the HealthMate Jr. -- about the size of a small bedroom.

Runners-up in this category include two models from Rabbit Air. Both earn high praise from Sherbenou at Air-Purifier-Power.com and from users at Amazon.com.

Sherbenou says the sleek, slim Rabbit Air purifiers are beautiful, technologically advanced and supremely quiet, kicking into high speed only when sensors find the air polluted enough to make it necessary. The Rabbit Air BioGS SPA-421A (*Est. $330) uses three levels of filtration (prefilter, HEPA and charcoal), saying it is able to handle a 600-square-foot room. The Rabbit Air MinusA2 SPA-780A (*Est. $550) adds two filters (a second prefilter and your choice of a bacteria, pet dander or chemical filter) and says it can handle an 815-square-foot room. However, Sherbenou says these machines don't have the power to change the air very often in rooms that size. Rabbit Air also says its purifiers emit negative ions but no harmful ozone (often a byproduct of ionizing air machines). We couldn't find any objective source that has independently tested Rabbit Air's ozone output. Users at Amazon.com say they are pleased with the quietness, performance and great customer service of Rabbit Air. The MinusA2 SPA-780A earns a perfect 5-star rating in nearly 30 reviews, and the less expensive BioGS SPA-421A maintains a very high 4.5-star average rating in more than 140 reviews.

Lower-priced HEPA purifiers

In general, higher-priced air purifiers have better filters and larger fans, which enable more air to be processed through the air cleaner. According to reviews, the trouble with smaller, less expensive air purifiers is that they don't pull a sufficient amount of air through the unit. One of the least expensive air purifiers to receive good reviews is the Honeywell Enviracaire 50250-N (*Est. $195). This circular air purifier has a prefilter for odors (*Est. $14 for replacement filters that should be replaced every three months) and a permanent HEPA filter that needs to be vacuumed at least twice a year.

Air-Purifier-Power.com cautions that this permanent filter will have to be replaced eventually due to downgraded performance caused by multiple vacuuming. Reviewer Ed Sherbenou says he has been running his Honeywell 50250 (an older model without a permanent filter) for years, and "I don't have a speck of dust anywhere, even stuck to my TV screen." But without a carbon filter, the Honeywell can't filter chemical fumes and other really tiny particles that pricier air purifiers like the IQAir HealthPro Plus and Austin Air HealthMate can.

The Honeywell air purifier is designed for use in rooms up to 390 square feet. About 300 owners have reviewed this model at Amazon.com, giving it a rating of 4 stars out of 5. Owners say it cleans the air of dust very well, and they report breathing easier and getting sick less often since they started running the Honeywell. Some owners say it's noisy, although others say the noise is not bothersome and sounds like white noise or a soft fan. The Enviracaire 50250-N isn't Energy Star-rated; one consumer group estimates it uses about $130 worth of electricity per year, while some more efficient air purifiers use $50 to $70 worth per year.

No other air filter in this price range gets enough recommendations from reliable experts to be considered a best buy. The Whirlpool AP51030K Whispure (*Est. $300) does take the top spot in one major test, where it does a great job clearing the air of pollen, dust and cigarette smoke on either high or low speeds. It's a favorite among users at Epinions.com and Amazon.com, too. Unlike the Honeywell, the Whirlpool air purifier includes a carbon filter to catch smaller particles and odor, and experts say it's quieter than other air filters, even on high speed.. However, you have to change the Whirlpool's carbon filter every three months and the HEPA filter once a year; it all adds up to about $100 a year, promptly boosting the Whirlpool's long-term cost out of budget territory. It will quickly exceed the cost of the more capable Austin Air HealthMate, which can keep the same filter for five years -- and backs that claim with a five-year filter warranty.