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What is a CADR Rating? – Air Purifier Rating Scale Explained

The Clean Air Delivery Rate, or CADR, in short, is mainly associated with air purifiers. This rate is a statistical value appointed to an air purifier based on independent studies carried out by the Association of Home Appliance Manufacturers (or AHAM). AHAM has been determining the CADR ratings of air purifiers for over 30 years.

Air Purifier in a Room
Air Purifier in a Room

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How is CADR Determined?

An air purifier is given a CADR rating by using a fairly simple to understand procedure, that is named the ANSI/AHAM AC-1 standard which calculates the CADR specifications. The purifier is positioned in an examination room of 1008 cubic feet. Prior to when the air purifier is turned on, the quantity of pollutants within the room is determined.

The purifier is turned on for a duration of 20 minutes, through which period the quantity of pollutants is sporadically re-examined. At last, the decrease of pollutants is put in contrast to their organic level of decay.

Once this examination is done, testers provide the air purifier its rating. The US Environmental Protection Agency then provides the CADR rating for the air purifier model. This rating will be explained in another paragraph.

Airmega Air Purifier
Airmega Air Purifier

CADR and Air Purifiers

Buying an air purifier is an investment for you and your family’s health and well-being. We encourage you to evaluate the CADR of an air purifier when choosing a unit. On this page, we’ll try to come up with a answer for the following question: What is a CADR score or rating?

First of all, CADR stands for Clean Air Delivery Rate and it calculates the amount of air that an air filtering system cleans for a particular contaminant. The larger the CADR figures the more effective your device will clean the air.

Even though some brands don’t send their air purifier for 3rd party testing, we at HouseholdMe think that observing CADR outcomes should be key to your choice for an air purifier.

It is good to have an air purifier with a high CADR rating together with an advanced HEPA filtration system when buying such a device.

Among the questions that you can think of when you’re looking for air purifiers is “What Air Purifier should I purchase?” or “How much sound does the air purifier make?”. With regards to sound levels and air purifiers, this might be one of the hardest factors to assess in this industry.

There’s a diverse set of decibel scales that are difficult to evaluate to one another. With regards to taking a look at the sounds levels of an air purifier, it is wise to check out the total value of the sound levels.

To phrase it differently, look at the bigger picture. You want to always link the sound to the amount of clean air you’re getting from that particular sound level.

The most effective way of explaining efficiency and the amount of clean air you will get from your air purifier is making use of the Clean Air Delivery Rate measurement. Once you are seeking a particular decibel score for an air purifier, you need to consider the amount of clean air it provides.

Black Air Purifier from Coway
Black Air Purifier from Coway

With regards to suggestions on evaluating air purifiers for sounds levels or whenever you’re evaluating tech specifications online or from brochures, search for DBA values. DBA levels are more easier to understand compared to decibels or any other measure. There are many apps for the smartphone available for you to download.

You’ll be able to quite easily examine the noise levels of the air purifiers that are right in front of you. You can also try to find an independent info provider. A person who has examined appliances in a similar fashion and isn’t affected by any marketing and or sales.

We would like to emphasize on customer reports. Each and every second year these reports test air purifiers available in the United States.

They are testing sounds levels and efficiency on the maximum speed level and in addition, they test on the minimum, more significant level. The levels which everyone is using the most when turning on the air purifier. Customer reports study for both CADR as for noisw levels.

Even more important, needless to say, is that you want to check the noise level on your own and give it a try. Try to look for a store who offers air purifiers, so you’re able to switch them on and hear them for yoirself. You will notice how they appear to be on the separate speed levels.

You are able to evaluate air purifiers to one another according to efficiency. That’s the perfect examination to ensure you will get an air purifier that suits you. To evaluate the efficiency of an air purifier you also have to consider the CADR.

As said, the Clean Air Delivery Rate is focused on finding out how much clean air the device actually generates in a particular time period. It is not merely about the effectiveness and/or the flow of air. It’s about the mix of these two.

Have a look at our Recommended Air Purifiers

Buttons on an Air Purifier
Controls on an Air Purifier

CADR Rating

The CADR score is the indicator that refers to the cubic feet of air purified from specific pollutants by the device each and every minute. It will tell you how effective the air cleaner is in minimizing the pollutants in your home.

In most cases, you will discover the CADR numbers on the label of the air purifier’s product packaging. It contains 3 figures symbolizing the most typical household air-borne pollutants: smoke, dust, and pollen.

The devices can vary considerably when it comes to the CADR rates. Try to contest the described info of an air purifier to another, developed by another company.

Using this method the rule of thumb is: the larger the figures, the quicker and more effective will the air purifier handle cleaning the air at home or in the office. The air purifiers giving good efficiency often have a CADR rating over 350. The air purifiers having the lowest results are the models having the CADR rating below 100.

Clean Air Delivery Rate Example
Clean Air Delivery Rate Example

In the example above, the 120 CADR score implies that the air purifier is able to filter out a variety of air pollutants in 120 cubic feet per minute (CFM). As said, the larger the number, the quicker the air cleaner can purify the indoor air.

Initially, this method of ranking air purifiers appears to be easy and relevant: it offers you an recommended size of the room along with a sense of the purification abilities of the air purifier. But then again, the simpleness of the measurements supporting this score comes with some extent of controversy.

When estimating the CADR score for an air purifier, the air purifier is positioned in a 11 feet by 11 feet room with an 8 feet high ceiling, which is what we call a small room.

The room is totally encased, and the examination for pollen is finished within ten minutes. The dust and tobacco smoke examinations are finished within twenty minutes.

Simply because the tests are carried out in a tiny, encased room in just a short time period, the CADR score is likely to promote air purifiers that can circulate air fast.

Although the effectiveness of the filter also comes in handy, any air purifier with a minimal filtration level but high “flow of air” rate to move the air quicker has a greater score. Having said that, air purifiers with very effective filters that capture a lot more particulate matter but have a reduced flow of air rate will be punished.

Lots of brands are conscious of this drawback in the CADR score test, so these brands intentionally develop their air purifiers to optimize the “flow of air” level. There are distinguished air purifier brands that made the decision not to choose for a CADR rating carried out by AHAM.

Finger through Air Purifier Filter
Finger through Air Purifier Filter

CADR Rating for Dust

Regardless of the dimensions of your house or where it is situated, dust is a reality we cannot ignore. It forms on the furniture and other areas in homes. While trying to keep the dust away might feels like a struggle, there is still some hope.

There are actions you need to take to help minimize the quantity of dust at home, and among the more trusted is to make use of an air purifier.

What Makes up the Dust in Your Home?

Although you might presume dust is just gray dirt that just lays in your home, dust is a variety of many different particles that are found in many different origins. The precise structure of dust at home is as different as the family it lives in. A number of people, pets, and even how food is cooked, prepared and consumed plays a role in the kind of dust at home.

But then again, the majority of the annoying dust that builds up on your furniture comes from outside of your house. Mold spores, pollen, dirt, and organic debris all come into your home through open windows and doors along with shoes and clothes.

Even though these small particles are safe to the majority of folks, particular health issues, including asthma or allergies, could be set off by breathing or contact. Additional unsafe compounds, including lead, bug killers, arsenic, and tobacco smoke can also move into your home and on your shoes and clothes.

Dust is furthermore made up of shed skin cells, pet dander and hair from places indoors. Some of the dust even comes from small insects.

Dust mites that enjoy our beds and other insects that fancy our trash leave by-products which set in on our flooring and furniture.

These elements merge to put together our dust at home. Although the dust has a variety of origins, its contaminants are also available in a variety of different sizes.

A few elements, including dust mites, even though nearly unperceivable to the human eye, are rather big when compared to others. Dust mites are measuring anywhere between 100 and 300 microns. Other elements are a lot smaller, toxic deposit from tobacco smoke is often as tiny as .01 micron.

Layers of Filters in an Air Purifier
Layers of Filters in an Air Purifier

How an Air Purifier Can Help with Your Dust Issues

These small molecules move via the air until these particles ultimately come on your furniture. An air purifier can help to catch these flying molecules before they are able to come in your house.

This will make the air easier to inhale, additionally it also helps to keep your home clean by limiting dust buildup on floors, home furniture, shelves, and any other areas. An air purifier with a true HEPA filtration system is one of the most hands-on ways to keep dust from becoming an issue at home.

Produced in the 1940s to take care of scientists during The Manhattan Project, HEPA filter systems are extremely effective in getting rid of even the smallest of particles out of the air. A true HEPA filter is in a position to secure particles as small as .3 microns in dimensions with 99.97% effectiveness.

This is a relevant way of measuring as .3 microns is the size of the particle that is most easily and frequently inhaled and directed towards the lungs.

As the air purifier disperses the air throughout a room, it takes in air and all the dust particles that are openly drifting in it. Before this, the small dust particles get captured in the filter.

Those molecules that get caught in the air cleanser’s filtering system are the particles that would’ve ultimately settled on the floors and furniture of your home as dust, or perhaps have triggered asthma and allergies. Even though an air purifier is unable to totally get rid of allergens and dust from your indoor air, it definitely helps when you use it frequently.

CADR Rating for Tobacco Smoke

For those who have a “smoker” at home, you need to make use of an air purifier to remove the second-hand smoke.

What is “Secondhand” Smoke?

A lot of people these days understand the negative consequences that smoking cigarettes may have on their own well-being. But then again, the dangers of direct exposure to recycled smoke are not always understood.

Recycled smoke is the smoke that’s released by a cigar or cigarette, along with the smoke that is coming out from the person that smokes.

Even though the smoke that will come straight from smoking is a lot more harmful as compared to secondhand smoke, the two include the same cancer-producing compounds and are for that reason damaging the well being of all people who inhale it.

Tobacco smoke covers countless of different chemical substances, hundreds that are regarded to have negative consequences on the health of a human being. From lung discomfort and allergic reactions to more severe and potentially fatal illnesses like heart problems and cancer. Recycled or secondhand smoke is able to take your life even though you have never smoked before

Modern Air Purifier White
Modern Air Purifier White

How Air Purifiers Reduce Secondhand Smoke

An air purifier operates by attracting air and using a filter to catch particles and chemical airborne pollutants, and then delivering purified air back into your room.

A lot of people are aware of how an air purifier helps to get rid of pollen, dust, and mold to enhance the quality of air, but an air purifier can also function to get rid of the recycled smoke.

Air purifiers getting rid of the unpleasant smells of smoking, but they also successfully catch the harmful chemical substances found in recycled smoke. They accomplish this using two methods. The very first method is by using a HEPA air filter. A HEPA filter is able to get rid of a large number of particles out of the air.

True HEPA filters successfully eliminate 99.97% of the molecules measuring 0.3 microns or smaller, the hardest size for air cleaners to eliminate.

Tobacco smoke consists of particles varying in dimensions from 4 microns to as small as .01 microns, most are able to be caught in the material of a HEPA filter. As the tobacco is burned and changes to smoke the molecules become smaller and are a lot more complicated for even a good filtration system to catch.

The most effective way to get rid of the small pollutants in recycled smoke is to use an air purifier at the same time a person is having a smoke instead of waiting till they’re finished. Air purifiers also fight recycled smoke by using an activated carbon filter.

Active carbon is developed by subjecting carbon to very high temperatures, triggering a more porous and boosting its surface area. The porous surface of active carbon takes in the smells and chemical substances as air moves through it.

Filters of an Air Purifier
Filters of an Air Purifier

CADR Rating for Pollen

People suffering from regular allergies have to endure a lot in recent years. Allergic reactions increase as soon as Spring is around the corner. Mild winters and early spring weather can cause these allergic reactions to increase.

How to get help? There is no proper answer to this question, but many homeowners are finding support with whole-home air purifiers. Air filters that operate 24/7 can be very successful against the most difficult allergies.

You shouldn’t keep your windows open during Spring time. Despite the fact that you may want clean air as soon as the winter is gone, you’re just asking for problems. If you have to open them to eliminate bad smells then do so when the amount of pollen is the lowest. This will be from approximately 11 am to 3 pm.

Also immediately after a heavy rain storm is possible, as the majority of the pollen should be secured on the wet areas outside. Air purifiers are good devices to combat pollen, although they solely perform in one room. You shouldn’t open your windows whilst making use of an air purifier.

Get a Whole-House Air Purifier

Transportable air purifiers can deal with small areas at home, but they will by no means do a comprehensive job of eliminating contaminants out of your home. To bring purified air and overall comfort in each and every room in your house, you’ll need a whole house air cleaner.

These advanced devices are also compact but diligent, and they can be combined effortlessly utilizing your HVAC setup as well. That enables these air cleaners to purify and filter the air during every circulation. Based on how many times your AC unit switches on, a whole-house air cleaner can purify the indoor air supply many times an hour.

Modern Air Purifier
Modern Air Purifier

Eliminate Pollen From Your Home

Some air filtration systems are developed to keep debris and dust from getting into your HVAC system, but only a few filter systems can catch tiny molecules of pollen. Luckily, many air cleaners can deal with pollen, getting rid of this sneezing material from your air system.

If you are prepared to spend money, we suggest buying an air purifier making use of a HEPA filter. For HEPA air purifiers have a look over here. These advanced air purifiers catch up to 99.97 percent of tiny molecules and some use even an electric charge to kill harmful bacteria.

Trap Secondary Allergens

A top-notch air purifier does not end with only removing pollen. What’s more, it catches pet dander, mold, and other typical contaminants. That means that you will breathe a lot more easily in the Spring and the entire year.

Modern White Levoit Air Purifier
Modern White Levoit Air Purifier

CADR Rated 100+

How to calculate CADR ratings? You might be thinking how to transform the CADR rating to anything useful like your room dimensions. Based on AHAM, they recommend you to simply take the CADR score and increase this by 1.55 to have the dimension of the room. According to a ceiling height of 8 feet. For instance, a 100 CADR scoring air purifier will purify the air in a room of 155 square feet.

The other way around, that is to find out your room dimension and to know the correct CADR you’d then break down your room square footage with 1.55. Let’s say your room is 250 square feet. Divide this by 1.55 and you will get the number 161. This implies you’ll need a room air purifier having a CADR rating of 160 or above. AHAM suggests you make use of the “CADR for tobacco smoke” to determine the room square footage.

AHAM Certified CADR

The Association of Home Appliance Manufacturers (AHAM) is a company that is helping and representing businesses providing home appliances that are meant for purchase in the US. The AHAM also produces and keeps you up to date with a variety of complex requirements and criteria certified by the American National Standards Institute (ANSI).

Business specifications including these make sure that brands’ home appliance efficiency and requirement objectives stay constant, hence customers have clear measuring methods they can make use of to determine which air purifier to choose from.

AHAM Certification

The term AHAM is the abbreviation of Association of Home Appliance Manufacturers. And CADR scores were formulated by this company. Kindly take note, that you’ll never come across a CADR score for a whole house air cleaner, the main reason is that whole house air purifiers are calculated in a different way as compared to transportable air purifiers. Companies such as the EPA are trustworthy, given that they are depended on the CADR score AHAM is providing.

How Do Air Purifiers Become AHAM Certified?

Air purifier producers can by themselves take part in the CADR official certification procedure by signing up at the AHAM-Verifide site. At this time, air purifying appliance manufacturers are not forced to get an AHAM certification, so make sure to look for the AHAM-seal when you are buying your next air purifier.

Person Opening a Coway Air Purifier
Person Opening a Coway Air Purifier

AHAM CADR Certification Seal

The moment approved to the CADR score evaluation, the AHAM is making use of its ANSI Standard AC-1 to start evaluating an air purifier. The AHAM organization is making use of a test room of 1,008 cubic feet in its CADR efficiency analysis (11 feet by 11 feet by 8 feet room).

Dust, smoke and air-borne pollutants are launched into the test area, and the air purifiers are switched on for 20 minutes before the team of reviewers evaluates a number of leftover contaminants. Examining the pollen is completed in a similar fashion except the air purifiers only run for 10 minutes. The remaining contaminants count ends up being the base for the CADR score.

It is good to know that the majority of air purifier producers are not participants of AHAM (and therefore not having a CADR score) – but that is not particularly a negative thing. Because of the way the CARD is determined, lots of crucial efficiency attributes are not considered, and although a high-grade CADR score is certainly a benefit, other air purifiers are not portrayed correctly with only the AHAM score.

Issues with the CADR Rating

The majority of air purifier brands are showing their Clean Air Delivery Rate (CADR). Since 2 factors are utilized to determine the CADR score, a boost in one can balance out a decline in the other variable, but even end up in a greater CADR score. The CADR is intended to be unbiased and is marketed as the most effective way to evaluate air cleaners. Our major issue with the CADR scores is that they are taken by choice.

Brands aren’t expected to send in air purifiers for evaluation. There are lots of reputable air cleaners that were not handed in for evaluation. Although these air purifiers do a good job, a CADR rating isn’t offered to them and You’ll notice that we advise air purifiers without having a CADR score. For the reason that we understand that these air purifiers purify the air very well. Keep in mind, CADR ratings are simply guidelines you can apply. They aren’t the primary factor to think about when buying an air cleaner.

Touching the buttons on an Air Purifier
Touching the buttons on an Air Purifier

How to Manipulate the CADR Rating

A CADR rating is essentially just a way of measuring how fast air cycles through a presented air filter. Although this number is possibly important for most filtration-exclusive units trying to purify air only using one or two filter types, it is worthless as filtering the air is merely just one component.

Truth be told that the CADR rating doesn’t explain anything about how good, and sometimes even “if”, an air cleaner will filter bacteria, viruses, and other dangerous biological substances nor will it evaluate how good the air purifier cleans smells and chemical gasses.

The least complicated way to imagine this is that, despite the fact that a lot of brands in the business pertains their units as an air “purifier”, truth be told that most of the competitive units around are basically air “filters” that aren’t using anywhere close to the amount of extra “purification” innovation out there, for example, UV light, TiO2, active charcoal, negative ionization, and so on.

Reality is, when a brand is planning to advertise their particular air purifier based on the CADR rating, you can basically just “enhance” the speed of the fan, remove particular innovations and design the same minimal filter technology the majority of businesses are using.

For instance, when you take the air out too fast using an air purifier, to be able to unnaturally increase your CADR rating, any kind of UV technology that safeguards your household from dangerous viruses and bacteria that conventional air cleaners overlook, may contradict any results of eliminating viruses and bacteria.

A few Other Features Worth Considering When Buying an Air Purifier

Combined with the marks and seals guaranteeing you that the air purifier will function as it is stated, there are all kinds of other essential qualities that will be great to consider before buying an air cleaner.

White Air Purifier
White Air Purifier

The Filter Type
The air filtration system is the key element of any air purifier. More often than not, the filter type isn’t only made use of in the air purifier but instead in combination with a few other elements for better results.

The popular kinds are active carbon with particular chemi-sorbents, anti-bacterial, germicidal, HEPA, and the so-called Prefilters. All of them catches only a particular type of pollutants, therefore when mixed collectively, they are able to take out just about all types of air-borne pollutants found in the air at home or in your office.

Microorganisms and VOCs
Many people buy air cleaners to decrease the amount of floating harmful molecules in the air at home that can worsen asthma or allergies. But then again, it might be helpful to have an air filter dealing with mold, germs, and viruses that can trigger health issues.

The Volatile Organic Compounds might gradually harm you at the same time, being given off by glues, paints, and adhesives that are kept in the storage. Choosing an air purifier ensures the filter system can remove chloride, formaldehyde, and other dangerous VOCs.


Air Recommended Air Purifiers

Our Pick Perfect for bedrooms, playrooms, and living rooms, the Coway Airmega AP-1512HH is one of the best-performing, most durable, and most economical purifiers we’ve tested.

Most Popular The Levoit Core 300 air purifier has some strong suits, but in our opinion it falls short of carving out a meaningful niche for itself. Its ideal use would be in a small bedroom occupied by someone who is sensitive to noise.

Also Great With high end air cleaning performance and a whisper quiet fan, the Winix 5500-2 is the perfect combination of power and finesse. It cleared airborne particulates out of our smokey testing room faster than any other model.

Best of the Best If you have a large space you want to remove irritants from, We recommend the Airmega 400S. All of Coway air purifiers do an excellent job of attacking indoor pollutants, and we highly recommend any of them. The 400S is designed to accommodate large room sizes.

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About the author

Hi I’m Alex, founder of HouseholdMe.com and I’d like to say thank you for dropping by. Like most of you, the first thing I look at before buying something online is reviews or buying guides. By reading what other people say will help me gauge whether or not a product is good or not.  I am trying to help people find answers, solve problems, and get inspired.

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