HVAC Filters

HVAC Filters2024-02-13T13:01:23+00:00

HVAC Filters

On average, people spend up to 90% of their time indoors, and indoor air can be two and a half times as polluted as outdoor air.

Indoor Air Quality is of particular concern for those affected by asthma and allergies, but a healthier home is of broader benefit to all.

The asthma & allergy friendly® Certification Program seeks to assist people to identify products which will make a genuine difference to their indoor environment. It develops certification standards for relevant categories of products, and all certified products undergo testing to those standards. In this way, the consumer can then make an informed choice about materials like insulation, flooring products, etc. that they bring into their home.

In the case of HVAC filters, we test the product in an environmentally-controlled test duct, using test dust that contains allergens. It is important that the filter can remove allergens from the air. Different allergens respond differently to filtration, because they have different sizes and features. Our standard addresses these issues. We also test the filter when it is loaded with dust, to make sure its performance is maintained.

Our HVAC filter standard is one of over 50 standards in the asthma & allergy friendly® Certification Program, covering appliances, bedding products, air filters, building products, and services that can have an impact on the indoor air environment. You can explore the HVAC filter standard in more detail using the menu on the left, or use the links above to explore other standards.

Brand Promises for Healthier Home: An Interview with 3M

It’s no secret that consumers are demanding products that are safer and healthier for themselves and their families. But many brands are capitalizing on this by making health claims that are scientifically unfounded. What separates the companies that are delivering on their brand promise from the ones that are not, and how can companies tighten their messaging to cut across the noise?

Here, Allergy Standards’ VP of Business Development, Courtney Sunna, interviews leaders, brand managers, and marketers who are part of a global movement towards healthier products that are rooted in rigorous science. In this interview, meet Carrie Sazama, Senior Brand Manager at 3M, who helps breathe new life and fresh ideas into home air filters for one of the world’s most innovative companies.

Courtney Sunna: Consumers are constantly bombarded with everyday “dangers” to be wary of. Is poor indoor air quality really that big of a threat?

Carrie Sazama: Consumers should certainly be aware of indoor air quality! The U.S. Environmental Protection Agency (EPA) has ranked indoor air pollution among the top five environmental risks to public health. With Americans spending, on average, nearly 90% of their time indoors, it’s never been a better time to start caring about your indoor air quality. Yet awareness of poor indoor air, its risks and common causes, and simple ways to improve it are alarmingly low.

Even well-maintained and ventilated homes may have dust, pollen, mold spores, bacteria, and other viruses in its air.

Choosing the right filter is one simple way to help improve your home’s indoor air quality. While you can’t always see unwanted airborne particles, Filtrete® Healthy Living filters use exclusive 3-in-1 technology from 3M to pull in and trap unwanted particles, while letting cleaner air flow through.


Courtney: Why are third-party Certification Marks important for your brand?

Carrie: Filtrete Brand’s team of scientists continuously seek ways to innovate the category with cutting-edge technology.

In addition, the brand frequently conducts internal and independent testing – like the asthma & allergy friendly® Certification Program – to ensure the products meet high standards and evolving consumer needs.

Having third-party certification marks helps give the consumer peace of mind that they are taking a proactive step to help reduce airborne allergens from the air passing through their home’s filter.


Courtney: How is Filtrete® Brand helping consumers become more engaged with the quality of their indoor air?

Carrie: To help consumers take control of their home’s air, Filtrete® Brand is launching the Smart Air Filter, the first-ever Bluetooth®-enabled HVAC air filter. When paired with the Filtrete® Smart App, it’s designed to remind you when it’s time to replace your filter, provide helpful tips on how to improve indoor air quality, show outdoor air quality conditions, and more.

People with pets, asthma, allergies, and/or respiratory issues have more specific air quality considerations to keep in mind. The new Filtrete® Smart App takes these factors into account and bases data-driven tips and alerts accordingly.

Filtrete® Smart Air Filters will be available at participating retailers in spring 2018.


Courtney: How do you focus on building long-term trust and loyalty with consumers?

Carrie: For more than 25 years, Filtrete® Filters have delivered cleaner air to millions of homes. Helping people get cleaner air for themselves and their family is our top priority. Because every breath is important, the Filtrete® Brand created Filtrete® 365 to help people get smart about their home environment through personally-relevant insights. The Filtrete 365 Program’s goals are to help people choose the correct filter while also strengthening brand loyalty through the distribution of personalized content. Filtrete 365 also sends custom filter change reminders, through both SMS and email, based on their lifestyle and weather in their area. Filtrete® is committed to helping you create a cleaner, healthier, and fresher home environment.


Courtney: Thank you. 


About 3M Filtrete: For nearly 25 years, Filtrete Brand has been helping homeowners make every breath count by delivering cleaner air to millions of homes. Developed by 3M scientists and engineers, Filtrete Electrostatic Air Filters are designed with exclusive Filtrete Brand 3-in-1 technology from 3M that pulls in and traps unwanted particles — such as dust, pollen, mold spores, bacteria and viruses — while letting cleaner air flow through. Filtrete Filters are consistently rated highly by a leading magazine that rates consumer products.

Standard Abstract : HVAC/ Furnace Filters

HVAC/furnace filters that are Certified asthma & allergy friendly® are tested to the ASP:08-03/102 HVAC/Furnace Filter Certification Standard. The Certification Standard utilizes an algorithm of proprietary and recognized scientific techniques to assess filters for their ability to reduce allergenic and irritant materials. Submitted HVAC/furnace filters that pass certification testing are granted a certificate stating that the particular filter meets the requirements for the asthma & allergy friendly® ASP:08-03/102 Certification Standard.

Allergy Standards Ltd (ASL) subjects the HVAC/furnace filter to allergen measure based performance testing to ensure that the filter reduces total allergen burden that remains airborne. Assessment for certification requires that the filter be evaluated in terms of indoor allergen levels that are representative of those found in both air and surface samples of typical homes. The asthma & allergy friendly® Certification mark is awarded to those HVAC/furnace filters that have been scientifically demonstrated to contribute to the goals of allergen reduction.

 Media based filters alone are considered in this protocol number. Other technologies are not eligible for certification under this standard.

Part 1: Evaluation of the capability of the filter to remove allergens from the air flow in a defined space

A specified minimum percentage of the introduced allergens, that are found in people’s homes, must be demonstrably removed from the air flow by the filter. For particles <1.0µm (microparticles), particle counts rather than allergen measurement are utilized in the assessment.


% Reduction

Pollen (Phl p 5)


House Dust Mite (Der p 1)


Cat (Fel d 1)


Microparticles (0.3 – 1.0 µm)


Part 2 Evaluation of loading

As the filter becomes loaded with particulate allergen the air flow may decrease, adversely impacting on performance and increasing energy consumption. The filter is loaded with twice the dust that would be expected to accumulate in an average home over a three-month period. Air flow per unit of pressure drop is measured during loading and must not decrease more than 20% from that established for a clean filter.

Filter change recommendations are based upon data established through this assessment.

Part 3 Evaluation of seals

A similar set-up to the Parts 1 and 2 testing is amended to assess air by-pass when the filter is in use. Seal/by-pass is reported as pressure decay rate. The greater the decay rate, the greater the extent of the leak. The test is carried out on triplicate samples of filters. Air by-pass must remain <10% in 30 seconds.

All CERTIFIED asthma & allergy friendly® HVAC/furnace filters are associated with a unique Certification code.

Why and how we certify HVAC and furnace filters – a Q&A

There is ever-increasing awareness of the chemicals and allergens we come into contact with every day, particularly if you or a member of your family has asthma or allergies. We created the asthma & allergy friendly® Certification Program to help you improve your indoor environment by identifying products and services that can help to reduce allergens and create a healthier home environment.

But what is it that makes some HVAC/furnace filters better for the indoor environment than others, and where do we draw the line to decide to certify a HVAC/furnace filter as asthma & allergy friendly® ? We hope that the questions below will clarify this. Let us know if you have more questions!

Why do we certify HVAC and furnace filters?

Our goal in the asthma & allergy friendly® Certification Program is to create a healthier indoor environment for you and your family, as well as to reduce allergens in the home. So we look at all elements of the indoor air environment.

Heating, ventilation, and air conditioning (HVAC) and furnace filters are important elements of climate control in homes. These systems are mostly used to regulate temperature in the home, and sometimes also humidity. They work by forcing air through ducts to move it throughout the home.

Because of this movement of air, it is also possible for these systems to transport allergens and other small air particles throughout the home. Pollens, mold spores, and animal dander can all be spread through the home in this manner. So having effective filtration of the air passing through a climate control system is very important in maintaining a healthy indoor environment.

How do we test HVAC/furnace filters?

We use a standardised test duct to test these filters. This is a controlled duct where the filter can be inserted at the centre, and air can be forced through it. We can introduce dust containing allergens in the ‘upstream’ part of the duct. This air is then pressed through the filter, and we can test the ‘downstream’ area past the filter to see how much allergen and dust has passed through the filter.

1. Removal of Allergen

We introduce a specific amount of test dust that contains pollen, house dust mite allergen, and cat allergen into the test duct, and a blower forces the dusty air through the filter. When the air passes through the filter, we test it on the other side to see how much of the dust and the allergen passed through. We require that at least 95% of the pollen is captured by the filter, at least 92.5% of the house dust mite allergen, and at least 85% of the cat allergen. The difference between these numbers is because cat allergen particles are the smallest of the three allergens, and pollen is the largest. We also measure the tiny micro-particles in the dust, and make sure that at least 50% of them are removed by the filter.

2. Seals

The centre of your filter can be the best filter in the world, but if the seals around the edge are weak then the air and allergen can pass around the filter and be spread throughout the home. To test this, we cover the filter media with an impermeable film. We then insert the filter in the test duct, and challenge it with pressurised air to see whether the air passes around the impermeable filter. We make sure that the air by-pass is less than 10% in 30 seconds.

3. Loaded Performance

It isn’t enough to only test a brand-new filter and check if it can remove allergens and small particles. Over time, dust can build up on a filter, which is why you need to change it every so often. But before that, it is important that even when it is loaded with dust the filter can still perform well. We challenge the filter with twice the typical dust load that would be expected in a home in a three-month period. We record the filter flow and the air pressure in the test duct before and after the filter. We make sure that the performance of a loaded does not drop by more than 20% compared to a fresh filter.

How often should you change your HVAC/furnace filter?

You should follow the manufacturer’s instructions for changing the filter. When a filter is certified asthma & allergy friendly®, we have determined the best frequency for changing the filter, to make sure that its performance won’t drop and that you can be sure it is still filtering the air properly. This frequency will be in the filter instructions.

What else do we certify?

We have over 50 different asthma & allergy friendly® certification standards for products and services, addressing all areas of the indoor air environment. Some of these relate to products which remove allergens and dust from the indoor environment, like vacuum cleaners, air cleaners, dehumidifiers, and washing machines. Some of them relate to products where it is important not to provide an easy home for allergens and that it is possible to remove allergen from them – like bedding, toys, and flooring. And some of them relate to household products that should make as little an impact on the indoor environment as possible – like flooring and paint.

You can find out which products are certified asthma & allergy friendly® and read more here: www.asthmaandallergyfriendly.com

How To Take Care Of Our Indoor Air?

Maybe you live in the city, maybe you have a family member with asthma or other respiratory issue, maybe you have just realised how polluted our indoor air is and want to live in a healthier home. Whatever the reason, you have come to the conclusion that you need an air purifier. Or, wait, is it an air cleaner you need? What about an air filter?

It’s a minefield out there when it comes to the terminology, technology, effectiveness and variety of models that you can choose from. How do you know what’s right for you? Let me try to simplify a few things for you.

What’s in a Name?

Most manufacturers use the terms air cleaners and air purifiers interchangeably. Some refer to air cleaners as the products with a HEPA filter and purifiers as those that use Ultra Violet light, negative ions or ozone to clean the air. Often the devices use a combination of these with the ultimate goal of removing pollution- particles and gases – from the air.

So, the technologies available are:

1. HEPA Air Filter

Simply put, this is a fine mesh with flaps folded bit like an accordion, that traps particles as air is pushed through it by a fan. It can trap 99.97% of particles 0.03microns or larger. That includes pollen spores, pet dander, dust mites and some bacteria. This is a great option if you have an allergy sufferer in the house.

There is a bit of maintenance involved in that the filter has to be changed every two to three months or its effectiveness deteriorates. Some devices have a helpful indicator to remind you that the filter needs changing. Most HEPA filters also have a prefilter that removes larger particles and prolongs the life of the HEPA filter.

On the down side, a HEPA filter will not remove odours, chemicals or gases. For that you will need an activated carbon filter.

2. Activated Carbon filter

Interestingly, one of the first applications of activated carbon was to clean dirty water in the early 1900s. Subsequently it was used in gas masks to protect soldiers from poisonous gas in World War 1. 

When carbon is activated it becomes porous like a sponge, creating tiny holes within the carbon where pollutants get stuck, never to be released. All sorts of problematic pollutants can be trapped by carbon – bad odours, chemicals, smoke – so they are particularly useful for people sensitive to poor air quality. For instance, those nasty VOCs that are released by new furniture, cleaning products or paints are eliminated nicely by activated carbon.

Maintenance is necessary and depends on the thickness of the filter as well as the nature of the pollutants. If cigarette smoke is the main pollutant, for example, the filter gets saturated faster and will need more regular changing.

Because a carbon filter isn’t especially effective at trapping particulate matter, they are often combined with a HEPA filter.

3. Ultraviolet Sterilisation

A UV sterilizer uses the same UVA and UVB rays emitted by the sun to kill moulds, bacteria and even some viruses. A UV purifier can work well in the kitchen or bathroom, where the heaviest bacterial load is.

4. Ionic or Electrostatic

These technologies have become a bit controversial as some may generate ozone. Ozone is harmless in small amounts but it’s crucial that you check how much a device produces as, if inhaled in large amounts it can be damaging, especially to the very young, the very old or those with respiratory illness. Avoid anything that creates more than 50-60 parts per billion. Look for certification marks for reassurance that your device is safe. 

These purifiers work by producing negatively charged oxygen atoms which combine with dust, pollen or any positively charged ion and bonds with them. The resulting heavier particle then falls to the ground or, depending on the type of device, is trapped on a special collection plate. An ioniser therefore doesn’t eliminate or absorb the contaminants and so there is the potential problem of the particles becoming loose and re-entering the circulation.

An advantage of this type of purifier is that there is no filter and therefore no maintenance cost. If there is an ioniser plate, then this can simply be wiped clean and reused. This should generally done about once a week. These devices work against the smallest of particles including dust, pollen, bacteria and pet dander. They also tend to be low cost.


Size and Positioning Matters

Sick building syndrome Indoor Air Quality Allergy StandardsWhile it may be tempting to invest in the less expensive devices, think first of your problem and your goal. A single activated carbon purifier may be the best solution for a smelly utility room but if your aim is to reduce allergy triggers for your family, then you must factor in your whole house. My kids typically throw their worn clothes on their bed (bedrobe!) or the floor (floordrobe!) so any pollen tracked in from outside is disseminated throughout the house. When we walk around, we stir up dust which then travels just about anywhere.

A single purifier will only clean adjacent rooms not connected by a door or wall. We spend most of our time in the kitchen, living room, bedroom, office and basement, so consider each individual room’s problems and its occupants before choosing the right device. Positioning can improve the function too- if its cigarette smoke, position your purifier where the ashtrays are. A purifier by the door can help filter air as it comes into the room. In general, keep the device in a place with high air flow to maximise efficiency.

Finally, in a living area where people are continuously coming and going a purifier must be keptrunning 24/7. In a room like a bedroom or office where the door can be kept closed, then it’s only necessary to run the machine when the room is occupied.

Medical & Lifestyle Author Dr Anna O'Donovan

Medical & Lifestyle Author Dr Anna O’Donovan

About Dr. Anna O’Donovan – Medical & Lifestyle Author

Anna is a mum of three children, one with allergies, and she suffers from allergies and asthma herself. She is a qualified doctor and worked as a General Practitioner and as a dentist for a number of years. She is also an award-winning author.


air care, indoor air, asthma, asthma triggers, allergy, allergy triggers, healthier home, HEPA, air cleaner, air purifier, air filter

Further Reading 

Air Purifier Maintenance, Sylvane, Click Here

Air Purifiers: The Good, The Bad, and the Ugly. Click here

8 Best Air Purifiers For Your Home, Forbes, Click here

Related Internal Links


Air is one of the most fundamental requirements for life, but is often unnoticed due to the fact that it is everywhere. Man-made and natural compounds can make air unsuitable for certain applications and people. In these circumstances, filters can be an excellent way to improve air quality, indoors and on the go.


People who suffer from hay fever should protect themselves from pollen and mold spores, and people who work in busy cities may wish to protect themselves from the pollutants that are ubiquitous in these environments. Filters can be an effective way to do this.

When discussing indoor air quality, the terms ‘PM2.5’ and ‘PM10’ are often used. PM stands for particulate matter and the number that follows it refers to the size of the particulate matter in microns. A micron is one thousandth of a millimetre, for comparison, the period at the end of this sentence is about 400 microns! Although both these types of particles are very small, PM2.5 are referred to as ‘fine particles’ and PM10 as ‘coarse particles’ (as they are larger). The primary sources of these particles are cooking, automobile emissions, dust and incomplete combustion (fires). When particles are inhaled, larger particles are normally captured by the hairs in the nose, however particles of size less than PM10 can bypass this defence. The smaller the particle, the deeper it can make its way into the respiratory system, and potentially the more damage it can cause. Particles that are defined as PM10 include dust, pollen and sea salt, particles defined as PM2.5 are generally particles emitted from fossil fuel burning such as coal, wood, rubber and other materials1.

In hospital environments high filter efficacy is required to ensure that vulnerable patients are not exposed to particles that may exacerbate their illness. For example, when hospitals are undergoing renovation, great care has to be taken to ensure that Aspergillus mold spores are not introduced into the breathing zones of immunocompromised patients. Due to their weakened immune system, certain strains of Aspergillus mold can cause serious disease and death2.

In the pharmaceutical sector significantly high spec filters are required to ensure that the particle number in clean rooms is kept as low as 12/m3 (in outdoor air the particle number can be as high as 35,000,000/m3)3. This level of cleanliness is required to ensure that products intended as medicines do not get contaminated in any way.

There are a range of different types of filtration systems:

  • Media based filters
    • Fiberglass
    • Pleated 
    • Washable 
    • HEPA
  • Electrostatic filters
  • Activated carbon filters
  1. Media based filters are a basically a solid material with holes. The holes allow air to pass through, but will prevent certain sizes of particles passing through. The size of particle prevented going through will be dependent upon the application for the filter. In the home, prevention of mold spores (2-20µm) may be sufficient while in a clean room, prevention of viral particles (0.1µm) may be required. Media based filters are used in vacuum cleaners, air cleaners, HVAC systems and so on. The type of material that is used in these filters will affect price and also performance.
    1. Fiberglass – this is one of the most affordable types of media based filter and is disposable. These types of filters are mainly focussed on protecting the air cleaning device from large particulates, rather than filtering out contaminants from the air.
    2. Pleated filter – are generally made from cotton or polyester, a higher number of pleats will result in a greater surface area and therefore greater filtering performance.
    3. Washable filter – some air filters may be washable, and while it can save money in the long run, you also need to factor in time to wash the filter and ensuring that it is completely dry prior to use. Replacing the filter while damp may lead to mold and bacterial growth
    4. HEPA filters – high efficiency particulate air filters are the most appropriate ones for people with allergies as they have the capability to remove small particles to a high efficiency. HEPA filters can remove in excess of 99.97% of particles and have a MERV rating (see Table 1) of 17 and above4.
  2. Electrostatic filters use an electric charge to stick the particles to metal plates. As the particles are drawn into the filter, they are given a charge, oppositely charged particles (positive and negative) stick to each other and so if the particles are given a negative charge, they will stick to a positively charged metal plate.
  3. Activated carbon filters are used to remove odours and volatile organic compounds from the air, but do not have any specific particle removal efficacy.

Media based filters are the most common type and can be used as a first line of defence against a range of indoor air contaminants. Maintenance of indoor air quality is essential for a healthy home and can be achieved using a range of approaches.

Heating, Ventilation and Air Conditioning (HVAC) systems

A HVAC system works by drawing in air from outside and delivering it to the home environment. Filtration is a key part of this process; pollen and fungal spores are all carried through the air as part of their natural dispersal process, and will find their way into a home. If you are allergic to pollen or fungal spores, the filtration part of your HVAC system plays a central role in maintaining good indoor air quality. Filters work by having a pore size small enough to prevent these allergens from passing through but that will still allow air passage. As the air is filtered, the pores can become blocked and make the system much less efficient, ultimately causing the filter to fail. As such proper maintenance and monitoring of HVAC filters in essential.

The type of media filter used for HVAC systems will have a direct impact on the purity of the air that is delivered to the home. Media based filters are often classified according to the MERV rating. MERV, or minimum efficiency reporting value, is a measure of the size of particle that the filter will remove. The higher the MERV rating, the smaller the particle that the filter will remove, and the greater amount of that particle that will be removed. For example, A MERV 5 filter will remove 20-34% of particle sizes between 3 and 10µm, this means that anywhere from 35-80% of these particles sizes (which include pollen and dust mite particles) will pass through the filter.

Selection of the correct filter should be carried out carefully, based on you and your family’s individual needs as well as your surrounding environment. While selecting the highest rated MERV filter may seem to make sense, there are a number of considerations. Higher rated MERV filters will cost more and this should be considered. In addition, if you live in area with a very high pollen count, it is likely that the pollen will quickly clog up a MERV 17 filter, leading to greater turnover of filters as well as reduced efficacy. If the filter becomes clogged and is not changed, a build-up of pressure across of the filter can lead to failure of the filter as the air forces itself through, or around the filter.

As the seasons change, the exposure of particles to the filter will also change. You should make yourself aware of this and maintain your filter accordingly. During Spring and Summer, pollen counts will be higher and will result in a greater load for your filtration system.

Car Cabin Air Filters

While there are few scientific publications on how long people spend in their cars, there does seem to be a general consensus that it is between 8-9 hours per week6,7,8. That is the equivalent of a full working day each week spent in your car. Because of this, it is just as important that you take care of your indoor air quality in your car, as well as your home. An essential part of maintaining indoor air quality in your car, is the car cabin filter. This filter keeps dust, dirt, pollen, bacteria, mold spores and exhaust gases from entering the ventilation system in your car. The filters are generally media based, and similarly to HVAC filters prevent passage of a variety of contaminants based on pore size of the filter. Also similarly to HVAC filters, car cabin filters can become blocked and so regular checks and replacement are recommended in order to make sure that they operate correctly. If a filter does become blocked, apart from potentially allowing particulate matter through, ultimately it will make the air conditioning system work harder and may cause mechanical failure9. Some filters may have an activated carbon element to them – this will help to prevent odours and exhaust gases from entering the car cabin.

Filters are generally recommended to be replaced every 12,000 miles, or at a regular service interval. However if you are driving in areas with heavy particulate or pollen load, they may require replacement more regularly.

HVAC-air-filters-indoor-air-Allergy-StandardsAir Conditioner Filters

An air conditioner at it most basic converts warm air to cold air, to keep the indoor air environment comfortable. It also affects relative humidity (RH); RH is the amount of water vapour that is in the air and should be maintained between 40 and 50%. If the levels drop below 40% the air can become very dry and affect the comfort of the room, resulting in dry and irritated eyes, flaky skin and also can dry out the mucous membranes of the respiratory tract. If the levels go above 50% they can start to provide an environment where dust mites and mold can proliferate. The relative humidity control impact of an air conditioner is therefore very important10.

The way in which air conditioners can help to maintain a healthy indoor air environment is by replacing warm air with cold, this is achieved through constant circulation of the air in a room through the air conditioning unit. As the air is drawn in, it is passed through a filtration system. This filtration system is generally media based, although may be in parallel with other mechanisms such as electrostatic precipitation.

Similarly to HVAC and car cabin filters, the pore size of the media based filters is an essential aspect to the efficacy of the filtration system. Filter pore size should be selected based on what you need to remove from the air. For smaller particles such as bacteria, higher efficiency filters are required. Maintenance of air conditioner filters is just as important as HVAC and car cabin filters. Should the filter become over-loaded, in addition to a greater power requirement to drive the air through, the filter may ultimately fail, providing you with little to no air cleaning capacity.

Filter Selection

The selection of the right filter is clearly very important. If you don’t have allergies, and are just concerned with indoor air quality, a lower grade filter in addition to a carbon filter would most likely be fine. If you need to be more proactive about your indoor air quality a HEPA filter would be a more appropriate filtration system. Electrostatic filters are also a fine entry level filtration system however would be mostly redundant where a high grade HEPA filter was in place.

There a range of certification systems that are available to assist consumers with making decisions on managing their indoor air quality. These may be based on the product as a whole (ie air conditioner) or filters as individual units (ie HVAC and car cabin filters).

aham sealCADR – The Association of Home Appliance Manufacturers (AHAM), established more than 50 years ago, represents the appliance manufacturing industry by through leadership, education and advocacy. Part of this role involves setting standards for the performance of these appliances, including air cleaners and filters. The standard for determining this is the Clean Air Delivery Rate (CADR). This measure defines the amount of clean air that an air cleaner delivers, based on scores for smoke, pollen and dust. The higher the CADR, the faster the rate of air cleaning. This CADR number, as mentioned above can be used to determine the size of room that the air cleaner is suitable for; the CADR of your air filter should be equal to at least two-thirds of the room’s area11.

asthma & allergy friendly® Certification program USA

asthma & allergy friendly® Certification program

asthma & allergy friendly®– The asthma and allergy friendly® Certification Program is operated by Allergy Standards in collaboration with the Asthma and Allergy Foundation of America (AAFA), Asthma Canada (AC) and is also operated internationally through a global certification mark. The program certifies a range of consumer products that they are more suitable for those suffering from asthma and allergies, based on their impact on indoor air quality. Their certification addresses both chemical and biological contaminants, as well functionality of the products.


ecarf-siegel-en-300x300ECARF – the European Centre for Allergy Research Foundation is a not for profit foundation that certifies products based on specific testing standards. ECARF certifies a range of consumer products, including air cleaners/purifiers. These are tested based on removal of both fine and coarse indicator particulates that would represent the size of bacteria, pollen, spores as well as much smaller particulates. The standard also allows for testing of ozone and noise emission13.



All food and drink that enters your body is tested to ensure that it is safe for consumption. A human could last up to 3-4 days without water14, and just 3-4 minutes without air15. This is how important air is to us, and yet the food and drink we consume is tested to a much higher level than the air we breathe at home. Taking some proactive steps to improve your indoor air quality is a way to ensure that you keep this fundamental life support as clean as possible. You should always educate yourself as fully as possible as to your own needs in terms of maintaining a healthy indoor air environment. Selection of products to support your indoor air quality can be difficult, however selection of products that are certified is certainly a step in the right direction.

Dr. Tim Yeomans photo

Dr. Tim Yeomans

About the author 

Thanks to Dr. Tim Yeomans for this insightful article.

Dr. Tim Yeomans is the Centre Manager for Shannon Applied Biotechnology Centre, a collaboration between two third level colleges in Ireland. Tim holds a PhD in Microbiology and postgraduate qualifications in Technology Commercialisation and Innovation Management. Tim has worked in research and development for 20 years, both in industry and academia. In his role in Shannon ABC, Tim is responsible for the scientific direction of the Centre, intellectual property management and business and technology development.


asthma & allergy friendly®, indoor environment, air filters, HEPA, car cabin, allergy, asthma, certification, allergy insights, healthier home, indoor air quality.


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  16. Medical Daily [online] Click here accessed Sept 2019

Related Internal Links

ASL Helps Shape the Future of Healthy Buildings at NeoCon and Design Days 2023

16 June 2023

ASL had a hugely successful few days at NeoCon and Design Days 2023 in Chicago

ASL to Share IAQ Expertise with the Design Industry at NeoCon and Design Days 2023

2 June 2023

We are looking forward to bringing our expertise in indoor air quality to NeoCon this month to help shape the built environment today and into the future.

ASL to Share New Research on Textile Flooring at EAACI Congress 2023

1 June 2023

ASL is excited to share the results of our new research on textile flooring at the EAACI Congress 2023

Dr. John Ryan delivered an impactful keynote speech at Pulire 2023

17 May 2023

Dr. John Ryan, CSO at ASL, addressed the Importance of indoor air quality and ESG needs in his impactful keynote speech at Pulire 2023

Dr. John Ryan at ISSA Pulire 2023, Addressing the Importance of Indoor Air Quality and ESG Needs

5 May 2023

Dr. John Ryan will speak at ISSA Pulire 2023 with a talk entitled 'Cleaning For Purpose Not Just Appearance.'

ASL Bring Indoor Air Expertise to BAU 2023

25 April 2023

BAU 2023 was a great opportunity for ASL to bring their expertise in indoor air quality to Europe, meet new clients, and catch up with Tarkett at their busy booth

You’ll Start Tracking Home Health Like You Track Heart Health; Dr. John McKeon tells Well+Good Why

16 December 2021

Dr. John McKeon, CEO of Allergy Standards, gives expert advice on tracking home health and why it makes perfect sense

Why regular laundry washing is important to maintain a healthy home environment

28 October 2021

Many people can be allergic to dust mites, pet dander, and other allergens that can build up in bedding, clothes, and other washable items at home. Taking care of these items by washing them regularly is a fundamental part of maintaining a healthy home environment.

NBC News Consults Dr. John McKeon

14 October 2021

In this NBC News article, digital editorial intern for Select, Zoe Malin seeks expert advice from ASL CEO, Dr. John McKeon, on indoor air quality and air cleaners.

Dr. John McKeon on Healthy Indoors Live

23 August 2021

Watch our CEO Dr John McKeon and President & CEO of the Asthma and Allergy Foundation of America, Kenneth Mendez, on Healthy Indoors Live with Bob Krell for a very interesting dive into the significant role a healthy indoor environment plays in our overall health & well-being.