What is a Good CADR Rating for an Air Purifier

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Updated Jul 7, 2022 6:09 PM

While shopping for a top-rated air purifier, you are likely to encounter several data metrics that purport to illustrate efficacy and efficiency. One of these terms you will see often in the advertising for an air purifier is CADR. What is a good CADR rating for an air purifier? Keep reading and find out.

KEY TAKEAWAYS:

  • CADR stands for clean air delivery rate and is a measurement created by the Association of Home Appliance Manufacturers (AHAM).
  • There is no hard and fast number when it comes to CADR, but AHAM suggests that the CADR should be at least two-thirds of the cubic feet per minute metric (CFM).
  • In other words, if an air purifier’s CFM is 200, make sure the CADR is at least 133.

What is CADR?

CADR stands for clean air delivery rate and it is generally used to inform consumers as to how quickly a given air purifier will clean the air of a room. CADR metrics are typically given in three categories: dust, pollen, and smoke. CADR tests are conducted by the Association of Home Appliance Manufacturers (AHAM). As a note, manufacturers do not have to list the CADR rating of an air purifier, as it is entirely voluntary. It can be a helpful tool, however, for companies to sell units.

Insider Tip

CADR stands for clean air delivery rate and it is generally used to inform consumers as to how quickly a given air purifier will clean the air of a room.

What is a Good CADR Rating?

This is tough because CADR tests are conducted in a sealed chamber with conditions that are completely dissimilar to what a typical consumer would experience. Generally speaking, AHAM has indicated the “two-thirds rule” when trying to figure out a good CADR rating. This rule specifies that an air purifier is considered to have an appropriate CADR rating when the number is two-thirds as much as the cubic foot per minute (CFM) rating.

How to Maximize an Air Purifier’s CADR Rating

There are some simple steps you can take to maximize your air purifier’s CADR rating. But before that, some other ways to maximize your air purifier’s efficiency include how long an air purifier takes to clean a room and what is the right CFM in an air filter.

Insider Tip

AHAM has indicated the “two-thirds rule” when trying to figure out a good CADR rating. This rule specifies that an air purifier is considered to have an appropriate CADR rating when the number is two-thirds as much as the cubic foot per minute (CFM) rating.

Run it on High-Speed

You will want to make sure your air purifier is running at its highest possible speed to maximize the CADR rating and overall effectiveness. In addition, you need to know what a pre-filter is in an air purifier since it captures larger-than-average particulate matter, such as pet hair before they get a chance to clog up the actual air filter.

Run it Continuously

Do not fear running your air purifier continuously, as modern units were built with this constant use in mind. If your air purifier is on 24/7, the CADR will increase. Be sure you replace all necessary air filters according to the manufacturer’s suggestions. You don’t want to find out what happens if you don’t change the air filter in a purifier.

Close Doors and Windows

Close doors and windows throughout the room in which the air purifier is operating. The CADR will diminish if the air purifier has to work through a lot of outdoor air.

Warning

if an air purifier advertises a CFM of 200, you should make sure its CADR is at least two-thirds, so 133 in this case.

F.A.Q.S

CADR Rating: Is it a good measure of air purifier quality?

It is a good measure of an air purifier’s overall effectiveness, which can work in tandem with quality. The CADR rating is independently verified and tested.


Do larger air purifiers have better CADR ratings?

Larger air purifiers can have a better CADR rating, as they tend to feature larger-than-average filters. You should also look at fan power, as this can also impact the CADR.


What settings should you run your air purifier on?

Run your air purifier at its highest setting for the optimum CADR. You can also experiment with different settings, as each home and room is different.



STAT: A HEPA-type filter can remove 90% of airborne particles while a true HEPA filter is at 99.97%. (source)

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