The RabbitAir MinusA2 air purifier.
Allergens, pollutants or nasty smells hanging around in your home? You may need an air purifier.
With so many models on the market, though, it can be tough to know if the air purifier you're considering will really work. To start, you'll want to be sure it meets some basic standards.
"Definitely if you're going to look for a good, basic air purifier, something that has a HEPA filter is a must," said allergist Jenna Tuck, chair of the American College of Allergy, Asthma and Immunology (ACAAI) Indoor Environment Committee.
HEPA stands for high-efficiency particulate absorption; to meet this government standard, the filter must remove 99.97 percent of particles 0.3 micrometers or larger. (For context, a fine human hair measures about 70 micrometers in width.)
Although some allergens and particles that cause respiratory problems are smaller than 0.3 micrometers, Tuck said, HEPA filters can remove particulate matter enough to ease symptoms for many people. [The 5 Most Common Allergies]
"The patient who probably needs [air purification] the most is the pet-allergic patient whose family refuses to get rid of the pet," Tuck told Live Science.
People whose noses are particularly sensitive to smell can benefit, too, but HEPA filters can't entirely eliminate odors. Turk recommends that people with breathing troubles, allergies or asthma talk to their allergists for advice on whether an air purifier could help them.
If so, the next step is to pick one. Live Science's sister site, Top Ten Reviews, has checked out some of the top air purifiers on the market. Here are their top three picks for cleaner air.
#1. Alen BreatheSmart
The Alen BreatheSmart is an Energy-Star certified unit with a HEPA filter that stands just over 2 feet high. It has a sleek white design, and a lighted button on top that turns blue when the air is clean and orange or red when the BreatheSmart air sensor detects particulates. The sensor automatically triggers faster filtration when it detects particles in the air.
The BreatheSmart can provide filtration for up to 1,100 square feet (102 square meters) of space. It includes an indicator light to alert you when the filter needs a change.
Noise: The BreatheSmart has four fan speeds. The lowest sounds like a whisper, while the loudest, at 56 decibels, is comparable to a box fan running on medium.
Coway's air purifier uses a five-filter system, starting with a pre-filter for large dust particles and hair; a medium filter for smaller particles; a HEPA filter; and your choice of one of four customizable filters to remove either smelly volatile organic compounds (VOCs), legionella bacteria, sand dust or viruses. (Users should note that unlike the HEPA filter, there are no federal guidelines regulating these additional filters.) The unit also has a filter specifically to deodorize air.
Coway's AP-1005AH model covers rooms as big as 236 square feet (21 square m) and is only about half as large as the Alen BreatheSmart, making it a good option for people with limited space.
Noise: The Conway's highest setting creates noise at 53.8 decibels, similar to the noise of a box fan.
#3. RabbitAir MinusA2
The RabbitAir MinusA2 is wall-mountable and Energy Star certified. It is only 7 inches deep, making it one of the sleeker options for air purification. The design won a "good design" award from The Chicago Athenaeum Museum of Architecture and Design. Depending on the model you choose, the MinusA2 can cover up to 815 square feet (75 square m).
The RabbitAir MinusA2, like the Conway, has multiple filters, starting with a pre-filter and medium filter to get rid of large particles. The purifier uses a BioGS HEPA filter, which is designed to reduce certain allergens above and beyond a typical HEPA filter. A customizable filter option lets you pick an additional filter to reduce bacteria and mold, pet dander, volatile organic compounds and odors. Finally, air travels through a charcoal filter to reduce smells.
Noise: The RabbitAir MinusA2 is noted for its quiet operation, reaching only 45 decibels at its loudest.