Choosing Your Next Air Purifier Protect yourself from allergens and contaminants with air purifiers Air purifiers can go a long way in getting rid of fungus, mold, dust and bacteria that can cause everything from sneezing to runny noses to illnesses.This guide will tell you about the kinds of indoor pollutants that a purifier can help combat, along with the specific types of air purifiers. Tip: When choosing an air purifier, the size of the room is one of the most important aspects to consider. SHOP ALL AIR PURIFIERS Purifiers can help protect against tobacco smoke and its odors; irritation to skin, eyes and lungs that come from indoor pollutants; and allergy-related symptoms from bold, fungus, pollen and pet dander. Consult the chart for details about different purifier types. Removes odors and unpleasant smells Filter will need to be changed when full Not effective against dust, allergens or microorganisms Collection plates must be cleaned regularly

Requires electricity to operate Available in both portable and whole-house configurations Not effective against bacteria and viruses HEPA stands for “High Efficiency Particulate Accumulation” Removes 99.97% of all particles 0.3 microns or larger in sizedoes air purifier help with dust Filter must be replaced every 12-18 monthssharper image ionic air purifier May be more expensive to maintainsalt water air purifier Not effective against gases, odors or viruses Causes particles to clump together and fall to the ground Fallen particles may make floors and walls dirty Removes extremely small particles Doesn’t use a filter and has no fan, making operation quieter Not effective against fungus, germs or some viruses

Bulb must be replaced annually Bulb should be cleaned periodically, as per manufacturer’s instructions The longer pollutants are exposed to light, the more effective it is Not effective against particulates, gases or odors Placement, Performance and Features Make sure the purifier is suitable for the size room you’re looking to protect, and look for a high clean air delivery rate – the cubic feet of air a purifier cleans per minute. Avoid placing a purifier in a room that’s too large for it to fully cover. Some devices, like UV purifiers, are installed directly into your HVAC system. You may need a purifier for each room you spend time in. Casters and handles make it easier to move portable units around. Improve the effectiveness of your air purifier and extend filter life by using pre-filters that trap large particles before air gets to the main filter. To ensure quality, look for purifiers that have been approved by the Underwriters Laboratory.

Filters with larger surface areas are more effective than smaller ones. The clean air delivery rate (CADR) indicates how many cubic feet of air a purifier cleans per minute. The more air changes per hour a machine provides, the higher the quality of air it creates. Multispeed fan: Allows you to increase or decrease the speed to help provide the proper number of air changes per hour in different-sized rooms. Quiet operation: Operates quietly so you can sleep soundly without sacrificing air quality. Automatic timer: Set your purifier to turn on and off automatically. Filter change indicator light: Lets you know when it’s time to change the filter. Personal air purifiers: Battery-operated units that you can hang around your neck to provide personal high-quality breathing space.Q. What’s the best way to clean the air in my home?A. Air researchers talk about the Rule of 1,000: anything released indoors is about 1,000 times more likely to be breathed in than something released outdoors.“

It doesn’t take a lot of something released indoors to cause exposure,” said Dr. Kirk Smith, a professor of global environmental health at the University of California, Berkeley. “Even in California, which has among the strictest controls on smoking and among the lowest smoking rates in an industrial country, a significant fraction of total pollution exposure is from smoking.”Indoor pollution is, in a word, potent. And our attempts to combat it often make it worse.“People think incense or candles are beneficial, but of course they’re not,” Dr. Smith said. “It’s just combustion, and the smoke has the same health effects as cigarette smoke.”As for air fresheners, “it’s just adding chemicals on top of chemicals,” he said. “We might not know the exact health effects, but why expose yourself?”Plants are overrated as air cleaners, said Dr. Richard Shaughnessy, director of the indoor air program at the University of Tulsa. “Many leafy plants can be allergen collectors,” he said.

“And the soil is wet, which can be a source of mild spores.” Before you begin an air-cleaning effort, ask yourself what you are combating. Dr. Shaughnessy said: “Consumers are usually responding to an odor in their house. It could be related to cooking, flooring, painting or even mold. These are all gases, and the portable air cleaners you see at the store are not very effective at removing gases.”But filter-based cleaners can be effective at removing pollen, dust or smoke, which have larger particles. Dr. Shelly Miller, an air-quality researcher at the University of Colorado, Boulder, said she bought a HEPA (or high-efficiency particulate air) filter-and-fan-based cleaner that helped combat forest-fire smoke at her parents’ home in San Bernardino Valley, Calif.Before buying the unit, which cost about $80, she said, she made sure it had a clean-air delivery rating (or CADR) certification from the Association of Home Appliance Manufacturers, which measures the amounts of pollen, dust or smoke the model can remove.

Some units are better at eliminating one pollutant than another, so the information allows consumers to pick the unit that best suits their needs. For a quick fix in less extreme situations, like high-pollen days, Dr. Miller suggests turning an air-conditioner into an air-cleaner by replacing the regular filter with a HEPA filter, and running the unit a few times. Look for a filter with a minimum efficiency reporting value, or MERV, of over 10, she said.In general, Dr. Miller said, she doesn’t advocate the use of air cleaners, which she considers the equivalent of using a broom to clean up M & M’s spilled on the floor. Or, as Dr. Smith put it: “The best way to not have polluted air is to not have sources of pollution in the house.”Dr. Miller, who lives in Boulder, Colo., with her husband, two small children and a malamute, said she had very little carpet, since “carpets can be a reservoir for all sorts of particles. We call it resuspension — where you walk on a carpet and particles become airborne again.