Three Things to Know Before Buying an Air Purifier

Air purifiers really do work—if you buy the right one.

Dog sitting beside air purifier.
Air purifiers can help pull pet hair and dander, among other things, from the air.Getty Images

Some people question the efficacy of air purifiers: How much difference can a little fan device really make? A lot, as it turns out. Certain air purifiers can filter out particles in the air, which could be really useful for those with allergies, asthma, or other respiratory issues. But it’s also important to keep in mind what they can’t do.

Medify MA-40W V2.0 Medical Grade Filtration H13 True HEPA for 840 Sq. Ft. Air Purifier, 99.9% | Modern Design - White

Simple Upkeep

This device has a tempered glass panel that’s easy to clean.Medify Air

The first thing to know about air purifiers is exactly what they are. Essentially, a classic air purifier is a fan with a very fine filter attached; it pulls in air from the room and blows it through the filter, removing certain particles. You want to be sure to get a HEPA filter—this is the industry standard. This type of filter is the only one that’s been thoroughly vetted by third-party researchers.

Medify MA-25 B1 Medical Grade Filtration H13 True HEPA for 500 Sq. Ft. Air Purifier | Dual Air Intake | Two '3-in-1' Filters | 99.9% removal in a Modern Design (1-Pack, Black)

For Larger Spaces

This model can clean a 1,000 square-foot room in an hour.Medify Air

So what exactly can a HEPA-filter air purifier do? Quite a bit, it turns out. They’re highly capable at removing certain types of particulates from the air, including dust, smoke, paint fumes, pet hair and dander, pollen and even some mold.

Blueair Blue Pure Purifying Fan 3 Speeds with Washable Pre-Filter Reduces Allergens, Dust, Pollen, Pet Hair

Stand-Up Design

This model removes 99 percent of airborne dust and pollen particles.Blueair

One important thing to note about air purifiers is that they can only filter out what’s actually floating around the air. That means that you’ll have to dust, vacuum and clean regularly, because larger particles (including dust and mold) will eventually float down to the ground, where a purifier can’t get to them. This is a problem especially with carpets and rugs, which can attract these particles.

Also Consider

Molekule Air Large Room Air Purifier with PECO Technology for Allergens, Pollutants, Viruses, Bacteria, and Mold, Silver

Bright Touchscreen

This model is designed for use in spaces up to 600 square feet in size.Molekule
Blueair Blue Pure 411 Air Purifier for home 3 Stage with Washable Pre-Filter, Particle, Carbon Filter, Captures Allergens, Viruses, Odors, Smoke, Mold, Dust, Germs, Pets, Smokers, Small Room

Quiet Operation

This small unit intakes air from 360 degrees around it.Blueair