Copyright 2007 Consumers Union of U.S., Inc. Yonkers, NY 10703-1057, a nonprofit organization. Reprinted with permission from the December 2007 issue of CONSUMER REPORTS® for educational purposes only. The information and images posted here are protected by the copyright laws. Reproduction, downloading, redistributing, or retransmitting without our written permission is prohibited. www.ConsumerReports.org. AIR PURIFIERS Filtering the claims Most people buy air purifiers to ease generators,” on the facing page.) The FDA, asthma or allergies. But despite prod- though, doesn’t consider air purifiers a uct claims, there’s little definitive med- medical device. And the ozone emissions ical evidence that purifiers help relieve of home air purifiers aren’t regulated by respiratory symptoms. Some may pose any federal agency. But as we went to a threat even to healthy users. press, California banned ozone genera- Electrostatic precipitators are the most tors for most uses, effective 2010. heavily promoted purifiers, accounting for Air purifiers that draw air through fab- about half of the models sold. Oreck and ric filters are among those that do the best Sharper Image versions are best sellers, job of removing dust and smoke from the despite their lackluster air-cleaning air without producing any ozone. Top- performance in our tests. Electrostatic KEEP IT CLEAN Our long-term tests show rated models such as the Whirlpool that you need to follow recommended precipitators trap particles by applying an Whispure, $230, performed better at their maintenance to sustain peak performance. electrical charge to them as they pass lowest, quietest speeds than many others through the unit and depositing them on did at their higher, noisier settings. But plates or filters.The process creates some They create large amounts of ozone by simple steps such as those mentioned in ozone as a byproduct. design and claim to use it to purify the air. First Things First could improve air qual- While ozone in the upper atmosphere We rated two such models Not Acceptable ity enough so that you don’t need a puri- protects us from the sun’s ultraviolet rays, because in our latest tests they reached fier. Other findings and issues: ground-level ozone is an irritant that can up to 20 times the voluntary ozone stan- Ozone is a growing concern. No aggravate asthma and lessen lung function. dard based on the limit set by the U.S. standard exists for acceptable indoor Another type of purifier, ozone gener- Food and Drug Administration for med- ozone levels generated by a nonmedical ators, are a growing part of the market. ical devices. (See “Not Acceptable: Ozone device. Underwriters Laboratories (UL) First things first. Air purifiers alone won’t clean the air or relieve asthma or allergy symptoms. TRY THESE STEPS FILTERS ELECTROSTATIC Basic steps can be more effective than air Best for trapping dust, PRECIPITATORS purifiers, according to experts, including the pollen, and smoke without Best for low operating costs. Some U.S. Environmental Protection Agency and emitting ozone, an irritant. do a fine job of removing dust, the American Lung Association. Less expen- But effectiveness varies pollen, and smoke. sive options include: considerably among But all create some ozone, which • Banning indoor smoking models. They typically cost can aggravate asthma and • Keeping pets out of bedrooms more per year for both decrease lung function. Models • Removing carpeting and other electricity and replacement filters. Portable with small fans or no fans are dust-mite harbors models tend to be noisy at high speeds, ineffective at removing dust and smoke. and do-it-yourself whole-house furnace • Opening windows whenever possible Models with a fan can be noisy at high filters were fair at best for smoke removal. speeds. Models with plates need more • Using outdoor-venting fans in the maintenance than filters. bathroom and kitchen How they work A fan pulls air through a • Maintaining heating equipment filter. Portable models typically use high- How they work An electrical charge is efficiency particulate air (HEPA) filters; applied to the particles drawn into the For more simple ideas, go to www.Consumer whole-house units use pleated fabric filters device. Then the particles are captured Reports.org/aircleaning. Avoid ozone gen- and are attached to forced-air systems. onto flat plates or filters. erators, which emit hazardous levels of ozone. They should be used only by profes- Price $100 to $800 for portables; $10 to Price $250 to $800 for portables; $400 to sionals after serious contamination from a $30 for better DIY whole-house filters; $1,150 for professionally installed whole- fire or flood, not for routine air cleaning. $200 to $500 for whole-house systems house models (plus $200 or more for (plus $200 or more for installation). installation). 48 CONSUMER REPORTS &Z DECEMBER 2007 • Expert • Independent • Nonprofit Not Acceptable certifies electrostatic precipitators using dustry and consumer groups, including Ozone generators the FDA limit of 50 parts per billion. But Consumers Union, the nonprofit pub- Makers of ozone generators often target that limit is under scrutiny. lisher of CONSUMER REPORTS, search for a home users with claims that the devices “Fifty parts per billion is by no means better way to measure the ozone some reduce allergens such as dust, smoke, universally accepted in the scientific com- purifiers emit.“You can get any results pollen, germs, and mold using “highly munity as being a low enough benchmark you want depending on how you run the activated oxygen” or “super oxide ions,” for ozone,” says Richard Shaughnessy, current UL test,” says Shaughnessy,who is leaving the fresh scents of thunder- Ph.D., director of the University of Tulsa’s on the committee revising the standard. storms and waterfalls in their place. Two Indoor Air Research Program and the au- In the past we used the UL ozone test, companies, Biotech Research and Eco- thor of an analysis prepared for the among others. But because of concerns Quest, go much further in their ads. The $850 EcoQuest Fresh Air uses Consumer Product Safety Commission on about the UL approach, we tested ozone- “exclusive ‘Space Certified’ ” technology research pertaining to the current limit.A producing purifiers using our own test in “used to scrub the air inside spacecraft,” recent study of outdoor air in 98 urban an airtight, unfurnished room.While that ads say. BioTech Research says its $230 areas, led by Michelle L. Bell, assistant won’t exactly reproduce the levels in your EdenPure Area’s technology is “used by professor of environmental health at Yale home, given the increasing concerns the federal government to purify air in University,indicated that even low levels about even low levels of ozone, it’s useful the Space Shuttle and the International of ground-level ozone were associated to have this worst-case scenario of ozone Space Station.” And ABC Radio broad- with increased risk of premature death. buildup in a room. caster Paul Harvey, who claims to use the Ozone has other risks. Studies in- EdenPure, describes it as “the best air purifier ever created by the hand of man” creasingly suggest that ozone creates IF YOU BUY AN AIR PURIFIER in an ad. other irritants as it reacts with household Consumers Union continues to urge But our tests found that even at the products such as scented cleaners and air the CPSC to set indoor ozone limits for all generators’ low everyday settings, their fresheners. Among these irritants are air purifiers and mandate performance ozone production quickly exceeded the formaldehyde, a carcinogen; acrolein, a tests and labels disclosing the results. CU 50 parts per billion (ppb) FDA limit for toxic irritant found in cigarette smoke; also urges the Federal Trade Commission medical devices. Purifiers aren’t consid- and ultrafine particles. “Picture ultrafine to investigate air-purifier ads to determine ered medical devices by the FDA. Ozone particle behavior the way you see ciga- the validity of health-related claims. If concentrations in our test room meas- ured about 650 to 990 ppb for the rette smoke behave in a lighted room,” you’re set on buying one, keep these EdenPure, depending on the setting. The says Charles J. Weschler, Ph.D., a re- points in mind: EcoQuest produced about 110 to 350 ppb searcher at the University of Medicine Consider whole-house models. at its normal and high settings and up to and Dentistry of New Jersey.“They hang Forced-air heating/cooling systems circu- 4,300 ppb at its “away” settings, which in the air for a long time. The concern is late so much air that they can overwhelm the company says to use only when you how easily the ultrafine particles are in- portable purifiers.Whole-house purifiers and your pets aren’t home. haled before they can settle.” are a better option. Better products range The U.S. Environmental Protection Germ-cleaning claims are oversold. from $10 to $30 for do-it-yourself filters to Agency warns that relatively low levels of ozone can cause chest pain and short- Many air purifiers claim to rid your home $1,000-plus systems that have to be in- ness of breath. Ozone may also worsen of airborne bacteria and viruses in addi- stalled by a pro.The latter are more effec- asthma and compromise the ability of tion to dust, pollen, and smoke. We ran tive at removing dust and smoke. DIY the body to fight respiratory infections. tests on five portable air purifiers that furnace filters do nearly as good a job of The EPA regulates outdoor ozone levels, made those claims. While our tests con- removing dust but aren’t as good at re- but there is no federal agency that regu- firmed that they reduce germs in the air, moving smoke.