Blueair CADR in an air purifier infographic
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March 10, 2023

What is Clean

Air Delivery Rate


Understanding the importance of air purifier efficiency

Clean air is vital for our health and well-being. With the rising levels of pollution, indoor air quality has become a major concern. Air purifiers have become a popular solution to improve the air quality inside homes and offices. However, not all air purifiers are created equal, and it's crucial to choose one that is effective and efficient. This is where Clean Air Delivery Rate (CADR) comes into play. In this article, we'll explain what CADR is and why it's crucial to consider when purchasing an air purifier. 

The Clean Air Delivery Rate (CADR) is an established standard defined by the independent Association of Home Appliance Manufacturers (AHAM) in the U.S. Certified and verified by an independent laboratory, AHAM uses CADR to assure consumers that an air purifier will perform according to the manufacturer’s product claims and helps shoppers easily identify which air cleaners work better than others. 

The program has become a globally respected performance indicator for air purifiers and is used by many leading air purifier manufacturers. Blueair is one of the member companies of AHAM and our air purifiers are tested according to the latest standards. All AHAM Verifide models and their performance can be found in the online AHAM Verifide database. 

Blueair a room with an air purifier and red smoke

What is Clean Air Delivery Rate (CADR)? 

Clean Air Delivery Rate (CADR) is a measure of an air purifier's efficiency in cleaning the air in a room, i.e. CADR measures an air cleaner's effectiveness based on room space and the volume of clean air produced per minute. This shows how well dust, pollen and smoke, the three most common indoor air pollutants are removed from the air you breathe.

Why is CADR Important? 

Choosing an air purifier with a high CADR rating ensures that it is effective in cleaning the air of pollutants, such as dust, pollen, smoke, and other airborne particles. A higher CADR rating means that the air purifier can clean the air faster, making it more efficient. On the other hand, an air purifier with a low CADR rating may not be as effective in removing pollutants from the air, leaving you breathing in harmful particles. 


For example, if an air purifier has a CADR of 388 for tobacco smoke particles, it will reduce smoke particle levels to the same concentration as would be achieved by adding 35 square meters of 100% clean air per minute.

Blueair infographic of Clean Air Delivery Rate CADR in an air purifier

Air distribution 

The Blueair air purifiers include a wide range of solutions and technologies to ensure that the air distribution to and from the air purifier is as good as possible. 


  • Intake + Outlet – For example used in the Classic, Pro and Sense+ ranges, utilizes the traditional set up where air is drawn into the air purifier via the intake on one side and exited from the air purifier through an outlet on the opposite side or on the top of the unit. This has the benefit of allowing the air purifier to be placed closely against a wall.  

  • 360-degree intake + Outlet – The models in the Blue range, draw in polluted air from all directions with a 360-degree intake and delivers the cleaned air through the top of the unit. This allows for big filters that can filter out more pollutants. The 360-degree intake additionally offers more freedom in where the air purifier can be placed, including corners. 

  • The patent pending SpiralAir™ technology, used in the HealthProtect™ air purifiers, focuses on the distribution of air from the air purifier and ensures that clean air is circulated to every corner of the room. The uniquely designed outlets, wrapped around the air purifier’s edges, offers 360-degree omni-directional airflow that makes it possible to place the air purifier anywhere in the rooms while still getting optimal clean air coverage.

How is CADR calculated? 

CADR is calculated using three measurements – smoke, pollen, and dust. These measurements are conducted in a controlled environment, such as a testing chamber. The air purifier is placed in the room, and the pollutant is introduced into the air. The air purifier's efficiency is measured by the reduction in the pollutant's concentration in the air after a specified amount of time. 


Providing a direct comparison between top-rated air purifiers, CADR is the only air purifier standard that is recognized as an American National Standard, since it allows for consistent comparison between AHAM certified products. CADR is also endorsed by the U.S. Food and Drug Administration and the Environmental Protection Agency.

Understanding CADR Ratings 

CADR ratings are provided for each pollutant, and a higher CADR rating indicates that the air purifier is more efficient in removing that pollutant. For example, if an air purifier has a CADR rating of 200 for smoke, it means that it can remove smoke from a room of 200 square feet at a rate of 200 cubic feet per minute.

High CADR and more, with HEPASilent™ technology 

Blueair HEPASilent™ technology delivers especially high performance and efficiency by combining electrostatic and mechanical filtration technologies. This combination, pioneered by Blueair, delivers high CADR with whisper-silent operation and high energy efficiency. In fact, a Blueair air purifier works so quietly that you can not only sleep next to it, you might even have to check to make sure it is switched on. And on its lowest setting, a Blueair air purifier, thanks to HEPASilent™ technology, uses less electricity than a small lightbulb, while still achieving a 99.97% filtration efficiency of airborne particles down to 0.1 micron in size. 


No other air purifiers deliver such high performance on so many parameters at the same time. 

CADR takes into account: 

  • Size of the particle removed 
  • Percentage of particles removed 
  • Volume of air passing through unit


Can CADR be used to compare air purifiers of different sizes? 

Yes, CADR is a standardized measure that allows you to compare air purifiers of different sizes. 


Is a higher CADR rating always better?  

It depends on the size of the room and the specific pollutants you want to remove. A higher CADR rating means that the air purifier can clean the air faster, but it may not be necessary for smaller rooms, so with room size in mind, you should choose the highest CADR for that size. 


What CADR rating should I look for in an air purifier?  

It depends on the size of the room and the specific pollutants you want to remove. The AHAM recommends a CADR rating of at least 2/3 of the room's area. 


In summary, CADR is an industry-standard measure that provides consumers with a reliable way to compare the efficiency of different air purifiers. It takes into account the size of the room and the specific pollutants that the air purifier can remove. When shopping for an air purifier, look for one with a high CADR rating to ensure it is efficient in cleaning the air of harmful particles. 

However, CADR is not the only factor to consider when purchasing an air purifier. Other factors such as noise level, filter replacement costs, and energy consumption should also be taken into account. It's important to choose an air purifier that meets your specific needs and budget. 


Air purifiers can significantly improve indoor air quality but choosing the right one is essential. Understanding CADR and its importance can help you make an informed decision when selecting an air purifier that will best suit your needs. So, when shopping for an air purifier, make sure to check its CADR rating and compare it to other models to make the best choice for you and your family's health. 


Clean Air Delivery Rate (CADR) is an important factor to consider when purchasing an air purifier. It ensures that the air purifier you choose is effective in cleaning the air of harmful pollutants, providing you with clean and healthy air to breathe. 

Ready to start your clean air journey?

Blueair air purifiers are simple to use and have something special: We are the only major air purifier brand to verify 100% of our models for performance for Clean Air Delivery Rate (CADR).

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