About Air Purifier Coverage Area

How square footage ratings are determined
for Surround Air purifiers.


Determining square footage is not an exact science, since there are many factors that will influence the amount of square footage an air purifier will cover. Plus, there is not a reliable method available for determining square footage coverage.

The Association of Home Appliance Manufacturers (AHAM) developed the CADR system (Clean Air Delivery Rate) in an attempt to create a standard for square footage coverage, but this methodology does not take all pertinent factors into account (about CADR).

Surround Air ratings are based on multiple factors, such as fan power, ratings of comparable models, and the types of technologies used (such as air ionization). With air ionization, negative ions are circulated into the air and throughout the room if adequate air flow is present, increasing the amount of square footage that can be covered.

It should also be noted that the closer you are to the air purifier, the more efficiently the air at that distance will be purified, regardless of an air purifier's square footage rating. The areas at the outer extent of an air purifier's effective coverage area will not be purified as thoroughly as the areas closer to the unit.

Keep in mind that the square footage ratings offered by Surround Air are merely a guide, and not to be completely relied upon. Once in your home, there are several factors that can influence the amount of square footage an air purifier will effectively cover, such as:

  • Pollution Level. The higher the pollution level, the lower the effective coverage area.

  • Air Flow. The greater the air flow in an indoor area, the higher the effective coverage area.

  • Floor Plan Layout. The more open the floor plan, the higher the effective coverage area.

  • Air Purification Technologies. With filters, the air must pass through the filter in order to be purified. With air ionization, negative ions are circulated through the room.