1. Filter efficiency
When selecting an air purifier, consider performance first. Compare air purifiers using the Clean Air Delivery Rate (CADR). This measures how well a system removes pollutants from the air. The higher the CADR test numbers, the better the unit cleans indoor air.

2. Capacity
Measure the size of the room where you want to purify air. Choose a unit that can handle the total volume of air in the room. Remember that high ceilings affect the total cubic footage. Use the Association of Home Appliance Manufacturers (AHAM) recommended room size to choose the correct unit.

3. Health concerns
Air purifiers can improve air quality for those with allergies, asthma and other respiratory conditions. Blueair’s HEPASilent™ filters capture 99.97% of the smallest particles from dust, pollen and pet dander to tobacco smoke and viruses.

4. Legitimacy of manufacturer claims
When comparison shopping, AHAM is the most reliable source of unbiased information. Blueair purifiers are AHAM certified in performance tests that are recognized as accurate and impartial by the EPA, the Federal Trade Commission and the American Lung Association.

5. Indoor environmental factors
Environmental conditions impact a purifier’s performance and maintenance requirements. Blueair’s HEPASilent™ filters counter mold and bacterial growth without filter sterilization or the addition of chemicals.

6. Operating cost
Check the manufacturer’s recommended filter replacement interval and costs. Generally, the most effective units are also the most costly to purchase and maintain on a daily basis. Look for the unit’s energy use, expressed as watts.

7. Construction quality
Check the warranty to make sure it covers internal components, such as fans and blowers. The unit should be certified for product safety by organizations such as the Underwriter’s Laboratory or ETL.

8. Ease of Use
Replacing filters and periodic internal cleaning can require weekly additives, filter washing, heavy lifting and special tools. Other air purifiers have maintenance regimens that simply require a filter change. Select an air purifier that meets your requirements.

9. Warranty
Make sure that the air purifier carries a solid warranty. Most established manufacturers offer warranties ranging from three to five years.

10. Bells and whistles