According to the NHAPS, Americans spend an average of 87% of their time inside buildings. Unfortunately, the air inside buildings may contain harmful pollutants such as volatile organic compounds (VOCs). As such, it is wise to install an air purifier in your home. Here are factors to consider when shopping for air purifiers.
Clean Air Delivery Rate (CADR)
In simple words, the Clean Air Delivery Rate indicates how quickly an air purifier can remove pollutants from the air in your home. According to the Association of Home Appliance Manufacturers (AHAM), this rate ranges from 0 to 450 (the higher the rate, the better). With this in mind, Consumer Reports recommends purifiers with a CADR of 350 or more.
Minimum Efficiency Reporting Value (MERV)
The Minimum Efficiency Reporting Value (MERV) is a metric developed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) to measure the efficiency of an air purifier in removing air pollutants from the air that passes through it. MERV ratings range from one (low) to 20 (high). As such, the rule of thumb is to choose an air purifier with a high MERV rating.
Air Purification Frequency
Select an air purifier that can handle your air purification needs. In this case, a good indicator is Air Changes Per Hour (ACH), which is a measure of how frequently the air in a room passes through an air purifier. Most manufacturers quote this rating in terms of room square footage. For example, an air purifier with an ACH rating of 4 for a 20” × 20” room can purify all the air in such a room four times per hour.
Some of the factors to consider when shopping for air purifiers include air purification frequency, the Minimum Efficiency Reporting Value (MERV), and the Clean Air Delivery Rate (CADR).