What is CADR and Why It is Important?

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In Brief: What is CADR and Why It is Important

CADR stands for Clean Air Delivery Rate. The CADR is a measure that indicates the volume of clean air delivered by an air purifier per hour or per minute. Ideal CADR values for different spaces are dependant on the area as well as recommended ACH values. AHAM which devised the CADR measure generally recommends that the CADR of your air cleaner should be equal to at least two-thirds of the room’s area.

Are you planning to buy an air purifier and is not quite clear about some of the technical parameters associated with air purifiers like ACH, CFM, CADR etc?

If so, you have come to the right place. This article will explain what is meant by the term CADR and why it is important in the context of air purifiers.

What is CADR and How it is Calculated?

CADR stands for Clean Air Delivery Rate. It is a measure to express how efficient purifiers are in removing particles.

In other words, this value indicates the volume of clean air delivered by a device during a defined period of time. The better CADR ratings are, the more powerful an air purifier’s fan is.

CADR values are usually expressed in cubic feet per minute (CFM) or in cubic meters per hour.

A device with a CADR of 400 cfm can provide 400 cubic feet of cleaned air every minute. The CADR of an air purifier depends on the power of the fan inside it.

CADR rating is expressed in CFM which stands for cubic feet per minute, or in m³/hour. CADR ratings were devised by AHAM (Association of Home Appliance Manufacturers).

AHAM measures the effectiveness in removing different particle sizes, three types of particles are tested:smoke, pollen and dust.

These represent small, medium and large-sized particles. Each is measured and assigned it’s own CADR score.

AHAM generally recommends that the CADR of your air cleaner should be equal to at least two-thirds of the room’s area.

Why is CADR Important for Air Purifiers?

CADR is a very important measure for air purifiers because this number informs us about the volume of clean air a device can provide per minute or hour.

Usually higher the CADR value it is better because the air purifier can provide more volume of cleaned air.

CADR value is crucial in determining the ACH of a purifier.

If the CADR value is too low then the device might not able to clean the air in a room the minimum required times as suggested by the recommended ACH values.

As the size of the room increases, the CADR value of the air purifier should also increase to ensure that an adequate amount of purified air is supplied.

AHAM as a general rule recommends that the CADR of your air cleaner should be equal to at least two-thirds of the room’s area.

This measurement helps buyers to compare various air purifiers and their suitability and efficiency for purifying air-specific spaces.

How to select the Right CADR for your Air purifier

When buying an air purifier it is important to ensure that the device is able to supply adequate air of clean air. CADR can be a very useful measurement in ensuring this.

The general advice by AHAM is to get a purifier whose CADR is at least equal to two-thirds of the room’s area.

For example, for a room with the dimensions of 20 feet by 12 feet has an area of 240 square feet, it would be best to have an air cleaner with a smoke CADR of at least 160.

If the CADR is too low then the device might not be able to supply enough cleaned air.

While high CADR is good to measure generally, it should not be the only consideration. Higher CADR value can improve ACH also and so generally while choosing an air purifier it should be ensured that the

CADR of the device will satisfy the minimum recommended ACH value for the space in which it will be used.

In short, the right air purifier should have a CADR rating that will ensure that it can satisfy the minimum recommended ACH value for the kind of space it will be installed in.

Should you choose Air purifier with high CADR?

In general, high CADR means a greater supply of clean air and this is never bad. But this does not mean that devices with high CADR are always the best option.

The required CADR for a device is determined by the size of the room, its nature/use and the recommended ACH value for it.

The CADR value should be high enough to ensure that the air in the room is changed at least the minimum required number of times, as suggested by ACH recommendations for the particular kind of space in which the purifier will be installed.

FAQs

Why is CADR important?

The CADR rating makes it much easier to tell how well an air purifier will perform when compared with other units that have undergone the same testing. CADR ratings are also useful because they show you how well an air purifier can remove several common contaminants, and how much clean air it can deliver.

Is higher CADR better?

In general, the higher the CADR the greater the amount of clean air an air purifier can deliver. But the ideal CADR requirement for a situation depends on the size of the room and recommended ACH values too.

What is a good CADR rating for an air purifier?

AHAM generally recommends that the CADR of your air cleaner should be equal to at least two-thirds of the room’s area. In general, a good CADR rating is one that ensures that the air in the room/space is changed at least the minimum number of times recommended by the ACH values for that type of space.

Summary

We hope that this article has helped you in creating a clear picture of CADR, its meaning, importance, and uses.

If you have further queries or doubts regarding CADR, please mention them in the comments section. If you found the article helpful and informative, please spread it around by sharing it.