What Is Clear Air Delivery Rate (CADR)?

If you’ve ever suffered through a stuffy, pollen-filled spring, you know just how important indoor air quality can be. And while many of us are familiar with the term “air pollution,” we may not know exactly what it means. In this post, we’ll take a closer look at Clear Air Delivery Rate (CADR); what is Clear Air Delivery Rate (CADR)? and why it’s important. Stay tuned!

What Is Clear Air Delivery Rate (CADR)?

CADR is a rating system for air purifiers. The acronym stands for Clean Air Delivery Rate, and it measures the number of particles an air filter can remove from the air per hour.

The CADR rating is determined by testing an air purifier with smoke, dust, and other airborne particles in a chamber. A machine then measures how many particles are captured in the filter when it’s turned on.

Thereafter, the air purifier can be compared to its CADR rating. CADR is measured in units of CFM, which stands for Cubic Feet Per Minute. The number of cubic feet refers to the air moving through the unit and the rate at which air is being processed. The CFM is measured using an airflow rate of 2.0 liters (3.5 US Gal) per minute, with no load. If the purifier has a fan, then the CADR is affected by the size of the fan.

How is CADR calculated?

CADR numbers are calculated based on the equation: by removing “air-cleaner turn on removal rate” from “natural decay rate of air particles” multiplied by the entire quantity (1,008 cubic feet) of the room. Alternatively, the calculation can be broken down as follows:

Cfm in CADR = [Rate air cleaner on – natural decay] x 1008 (Those living in countries that use metric measurements will be glad to know that volume and Cfm int meters are used as well).

The test’s rating is based on how fast a purifier can expel air (measured in cubic feet per minute) and how many particles it collects from the air, not including how many particles fall to floor space. That is to ensure that the test is more reliable.

Knowing the CFM, a factor is then utilized to determine an estimated space requirement the purifier will fulfill perfectly.

Air Filtering Standard:

The Air Filtering Standard is a way to compare the air purification capability of air purifiers, as it indicates how much dust or particles an air purifier can filter from the air per hour. It’s measured in CFM units. The standard also shows how many particles a machine can remove from the air over time but does not indicate what the machine will remove. The Air Filtering Standard measures how effective air purifiers are at removing particles. The standard, in short, means how fast an air purifier can filter airborne particles.

How CADR is Tested:

CADR ratings are measured using two different methods. One method is based on the unit being run at full speed and with the fan on high. The other method is to run the unit without the fan. In both cases, the air purifier is turned on for 20 minutes. This period is needed to ensure that the air purifier can completely remove particles from the air. In both methods, the CADR rating is determined by measuring how many particles are removed from the air while the unit is running.

The CADR rating is then calculated by subtracting the number of particles that would normally be removed if the air were not moving (natural decay rate) from the number of particles that are actually removed when the unit is running. Both measurements are made in cubic feet of air per minute. The first method is called the full speed method. The full speed method measures the CADR at its maximum performance, which is why it is called full speed.

CADR Rating Categories: Pollen, Dust and Tobacco Smoke

AHAM is the Air Hygiene and Health Association. It’s a nonprofit public service organization that tests air cleaner products for health effects on humans. AHAM basically establishes what is called “CADR” or Clean Air Delivery Rate for indoor air cleaners, which was an idea of the EPA to test the performance of air cleaners through a standardized test that yields a decent indication of the cleanliness of the indoor environment relative to specific contaminants which cause discomfort and health effects.

AHAM tests for three common pollutants: tobacco smoke, pollen, and dust particles. These are considered to be the major pollutants in most homes because they cause allergy symptoms or may affect those with asthma.

The AHAM CADR category for dust is 10-400. For pollen, it’s 10 to 450, and for tobacco smoke, it’s 10 to 450. Most air purifiers do fairly well in the “dust” or “pollen” categories but not so much in the tobacco smoke category because that requires more filtration but also because the test for tobacco smoke is more stringent and, therefore, air purifiers must be tested under stricter conditions.

Benefits of CADR:

There are some benefits of knowing the CADR rating of your air purifier, which includes:

It’s a lab-tested rating that ensures air purifiers perform their best.
It provides a rating that shows air purifiers’ cleaning effectiveness compared to other units.
The CADR rating is an effective way to find the best air purifier for your budget.
It can help you determine how much air purifier capacity you need.
It can help you make a smart purchase decision by comparing your needs against purifiers’ ratings.
The CADR rating can help you differentiate between the various air purifier models.
It can help you find the right purifier for your needs.
It can help you save money and time.

3 Objects of the CADR Rating System:

These objects are to inform the customers of a better understanding of the product that they are purchasing, from finding out how many CADR Units they need to having information about quality and performance. These three objects include:

1) Units for airflow

2) Factors that influence CADR and

3) The CADR test procedure.

The Air Delivery Rate Units:

The airflow unit is listed as a “CADR”. There are three different types of units for them: Room Size (up to 300 ft^3), Small Room (300-400 ft^3), and Large Room (400-550 ft^3). These CADR units will depend on the size of the room that is being tested, so they can effectively remove air pollutants in 1 hour.

Factors That Affect CADR:

There are many factors that affect CADR ratings for each unit, such as the model of the unit, the placement of the unit, and the clean air delivery rate of a certain filter.

CADR Test Procedure:

The test procedure to determine the CADR rating is to use a fan and draft method in order to provide data for the amount of air that can be removed from a room. The unit has to run continuously for 10 minutes, with the blower at high speed, and then repeat this process over again three times; each time, it will remove more pollutants from the air.

The Clear Air Delivery Rate (CADR) is a rating system for how effective the product is at removing air pollutants, which include pollen, dust, tobacco smoke, and mold spores. It also includes humidity control. The Association of Home Appliance Manufacturers (AHAM) created the CADR Rating System.

FAQs:

1. What is a good CADR rating for an air purifier?

Answer: The CADR is determined by the size of the room, so it varies. For small rooms, you want something with at least 100 CADR. Larger rooms require more filtration power, so the minimum is 200-300+. Typically, big rooms need around 230+ CADR to be sure they can get all of the particles out of the air.

2. Is CADR the same as CFM?

Answer: No. CADR is a rating of air purifiers, while the CFM refers to the volume of air moving through a system. However, a higher CFM will mean a greater CADR because airflow affects filter performance.

3. Is CADR the same as Filtration Efficiency?

Answer: No, but it is similar. CADR rates the purifier’s ability to remove pollutants from the air over time, while filtration efficiency measures how well a filter removes contaminants in real-time.

4. Is a higher CADR rating better?

Answer: Yes and no, depending on how you use it. For example, if a purifier is recommended for 300 square feet and its CADR rating is 200, the room should get cleaner air in five minutes. If a larger room needs 400 square feet but has the same CADR rating, then it might take 10 minutes. This is not a set-in-stone rule, but it is something to consider if you are planning to use the purifier in larger rooms.

5. What CADR do I need?

Answer: CADR is an important rating to consider when you purchase air purifiers. The CADR rate depends on the size of the room, though typically, a larger room requires a higher CADR rating for optimal performance. A good starting point is 100 for small to medium-sized rooms 200+ for medium-large and 300 or above for large rooms.

6. Is CADR 300 good?

Answer: Not necessarily. It depends on what you want it for and how much cleaning power you need. For big rooms or smoke and particles, 300 is a good number. If the room size is small and you just want clean oxygen, 300 CADR isn’t as impressive as if it’s for your living room which would be bigger than your bedroom.

7. What is a good CADR rating for dust?

Answer: It depends on the size of the room and how much filtering power you need. For small and medium rooms, 100-200 should be enough to avoid breathing in dust. If you’re talking about a big room with multiple people, then 300-400 CADR is better for catching all those fine particles.

8. What does CFM stand for?

Answer: CFM stands for Cubic Feet per Minute, which is the rate of airflow. This rating helps to determine how quickly air passes through an air purifier’s filters into the room. It also determines how many particles are caught in its filtration systems.

9. Which air purifier has the highest CADR rating?

Answer: Some of the highest CADR ratings come from Austin Air and IQ Air. They offer models with up to 500+ CADR, which means they can take care of rooms that are over 500 square feet in size.

10. What is a good CADR rating for a smoke?

Answer: Usually, 300 CADR is good for catching smoke particles. You may want a higher rating if you have multiple smokers or if the room is large.

11. How correct and useful are CADR ratings?

Answer: CADR is an important rating to consider when you purchase air purifiers. The Clear Air Delivery Rate(CADR) depends on the size of the room, though typically, a larger room requires a higher CADR rating for optimal performance. A good starting point is 100 for small to medium-sized rooms 200+ for medium-large and 300 or above for large rooms.

12. Why is CADR important?

Answer: CADR rates a purifier’s ability to remove pollutants from the air over time. It also measures how well a filter removes contaminants in real-time. So, it is important to consider when you are looking for air purifiers.

13. Do larger air purifiers have better CADR ratings?

14. Does the CADR have limitations?

Answer: Yes, the CADR is only an indicator of performance. It does not consider where you are located or what type of particles need to be removed. If you want detailed information, it is better to look for brands that offer more than one rating.

Conclusion:

In conclusion, the Clear Air Delivery Rate (CADR) is useful to measure how well an air purification system works for a certain size of the room to remove pollutants from the air over time. It depends on what you want it for and how much cleaning power you need.

For big rooms or smoke and particles, 300 CADR isn’t as impressive as if it’s for your living room which would be bigger than your bedroom. It also depends on the size of the room and how much filtering power you need.

For small and medium rooms, 100-200 should be enough to avoid breathing in the dust, while big rooms with multiple occupants might need around 200-300 CADR at least.

The CADR is an important rating to consider when you want to purchase air purifiers. It also measures how well a filter removes contaminants in real-time and helps determine an air purifier’s airflow and filtration efficiency.

However, it does not consider where you are located or what type of particles need to be removed. If you want detailed information, it is better to look for brands that offer more than one rating.