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What You Need To Know About CADR Air Purifying Rating

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Understanding The Importance Of CADR Rating In Air Purifiers

The demand for air purifiers has been steadily increasing, which is not surprising because of the pandemic. The device can clean indoor air with ease, providing the entire family with a layer of protection from the virus. It sanitizes the air of toxins, allergens, and pollutants such as tobacco smoke and dust. Hence, it is a necessary device in households with people suffering from respiratory conditions.

However, you have a wide variety of air purifiers to choose from, making it tricky to buy the right one. Likewise, there are important air purifier ratings you need to familiarize yourself with. One of these is the Clean Air Delivery Rate or CADR rating, which is what we will take a closer look at.

How Does The CADR Rating Work?

Simply put, the CADR air purifier rating, developed by AHAM, reflects the efficacy of an air purifier. It is a representation of the amount of clean air that comes out of an air purifier when it’s on the highest fan speed.

The certified rating aims to provide consumers an actual standard of evaluating the effectiveness of these devices at eliminating particles of various sizes. CADR rating utilizes cubic feet per minute or CFM in measuring the volume of air. It measures small, medium, and large-sized particles, which are given with separate scores:

  • Smoke (0.09 to 1 micron)
  • Dust (0.5 to 1 micron)
  • Pollen (5 to 11 micron)

Moreover, the rating scale of CADR is influenced by two factors:

  • Filter efficiency
  • Airflow through the unit’s filters

This makes the CADR rating one of the most vital metrics you have to look at when shopping around for an air purifier. That’s because it provides you an inside of the speed and how efficient a unit is.

How CADR Ratings Are Calculated

The Association of Home Appliance Manufacturers or AHAM conducts CADR tests. Air purifier companies give their units freely to the association for testing. AHAM applies the same test across all devices, making the CADR ratings consistent. Likewise, it offers a good measure of efficiency for air purifiers.

An air purifier is installed in a 1,008 cubic feet room to calculate CADR. Then, it is left to operate for about 25 minutes. Afterward, the levels of the free particles are measured and compared against their pre-test levels. Doing so allows for an unbiased measure of calculating how well a unit eliminates these different sizes of particles.

CADR To Room Size: What Is The Best CADR Rating?

The best CADR air purifier rating should meet at least two-thirds of the area of your room where you plan to place your unit. To get the room size, AHAM suggests taking the CADR rating of the air purifier you’re eyeing and multiplying it by 1.55.

For instance, if your living room measures 10 x 15 feet, then it has a 150 square feet area. Thus, the good CADR rating for it would be at least 100. Keep in mind that this is based on a room with a ceiling height of 8 feet.

Now, if you want to know the appropriate CADR and room size, simply divide the square footage of your room by 1.55. For example, dividing a room measuring 250 square feet by 1.55 will give you 151. So for a room this size, you need an air purifier with a 160 CADR rating or higher.

Moreover, AHAM advises applying the smoke CADR score when calculating a room’s square footage. The reason being it’s the smallest particle size measured. Hence, it’s the most challenging to obtain a high rate.

Particle Size Explained

As stated above, CADR is composed of three scores. In most cases, what you’ll see is the average rating of these in an air purifier. Dust, pollen, and smoke are a representation of airborne particles of these sizes.

For example, pollen CADR indicates large airborne particles that can be elements such as dust mites, pet hair, dander, and large mold spores. On the other hand, dust CADR is dust and pet dander that is finer in size.

Smoke CADR includes only particulate matter and does not include odor removal. Nevertheless, since it’s a reflection of the smallest particle an air purifier can get rid of, it’s the best value to apply for the removal of air pollution and smoke. Moreover, the AHAM does not have an air quality test for odor or gas removal. That’s why you won’t see any results for VOCs and other gases.

Advantages Of CADR To Consumers

  • It enables you to compare air purifiers objectively before making a final decision.
  • The measurements CADR provides are precise in terms of how good a device is at filtering out different particle sizes then overall capacity and airflow rate.
  • It’s an easy way to determine how well a device performs in comparison to others.
  • It shows the performance of the purifier when it comes to eliminating various common contaminants.

Does Every Air Purifier In The Market Have CADR?

While there are plenty of air purifiers that have a CADR rating, the entire rating process of AHAM is purely voluntary. That’s why some units out there haven’t been tested or carry a rating. Nonetheless, this does not necessarily make these air purifiers sub-par. Still, evaluating them can be a little challenging.

Does CADR Have Limitations?

Here are some vital things to know when looking at the CADR rating of air purifiers:

It does not include small particles

Clean Air Delivery Rate shows the overall performance of an air purifier. Nonetheless, it does not tell how effective a unit is against smaller-sized particles. You will find some with a high score rating because they are extremely effective at eliminating larger particles but not as good at removing tiny particles.

It does not measure gas

Gas is not included in the category of CADR. However, VOCs and similar gases can be highly dangerous to everyone’s health. In comparison to solid particles, a different method of filtration technique is required for these gases.

The air purifier is tested on its highest setting

Throughout the test, the units run on their highest setting. But the majority of homeowners do not often use this setting because of the level of noise air cleaners produce. Considering this factor is vital since you should not assume that your air cleaner will be as effective when it’s on its lower setting.

The test does not show wear

Like any appliance, your air purifier will wear over time. The test conducted by AHAM is under 30 minutes only. Hence, it will not show you when or how a device will diminish in its efficacy.

Are CADR Ratings Accurate?

The history of CADR rating is quite long. Also, reliable organizations such as FTC, EPA, and Consumer Union recognize it. So it’s a solid starting point when you want to know if a device is capable or not. Because of this, an air purifier’s rating is something you can trust whenever you’re shopping around for one.

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