Air Purifier Advice

Air Pollution – Not Just in Big Cities

Although for most people the term “air pollution” conjures up such images as smog hovering over a city or black smoke pouring into the sky out of heavy industrial buildings, the fact is that air pollution is an indoor phenomenon as well, and one that can affect unsuspecting people while they work, when they go out to eat or find entertainment, and even when they are in their homes. And though it is very easy to fail to notice it compared to more visible or dramatic threats to our well-being, indoor air pollution can pose serious health risks when we are exposed to too much of it.

2.7% of the entire global burden of disease is caused by exposure to indoor air pollutants – World Health Organization

The World Health Organization claims that 2.7% of the entire global burden of disease is caused by exposure to indoor air pollutants. This seems even worse when we consider how easy it is to take certain steps to reduce indoor pollution, such as not smoking, maintaining proper ventilation, and using an air filter.

Causes of Indoor Air Pollution

What causes this too-often overlooked phenomenon? There are many causes of air pollution in homes, workplaces, and elsewhere. These sources are very diverse and sometimes pose different kinds and degrees of health risks. To gain a fuller understanding of the magnitude of the problem, it will perhaps be helpful to examine some of causes of air pollution inside buildings.

Materials That Release Gasses

According to the U.S. Consumer Product Safety Commission and the Environmental Protection Agency, indoor air pollution primarily results from “sources that release gases or particles into the air.” These can include fairly common household combustion sources such as fireplaces and those chemicals that are used in indoor cooking, such as the gas in a gas oven. Other chemicals are released by building materials, most infamously asbestos, but also paint, certain types of pressed wood used to make furniture, and even wet carpets. Household cleaning or personal grooming products are other common ways that we introduce chemicals into our environment without giving the matter much thought. Heating and air conditioning devices can also contribute to indoor air pollution, as can humidifiers.

Second-hand Smoke

The consumption of tobacco while indoors also contributes to air pollution. As if the health problems that directly result from smoking were not enough, we must also consider the threat posed as a result of consuming tobacco products inside. Sadly, the health detriments of smoking do not stop when the cigarette (or cigar, or pipe) goes out. Exposure to second-hand smoke that has built up inside a home or business where smoking has occurred is highly dangerous.

For example, the EPA estimates that second-hand smoke is responsible for causing or worsening asthma symptoms for up to a million children every year, as well as causing respiratory infections that annually send thousands of children to the hospital and affect hundreds of thousands more. Among adults, second-hand smoke can cause problems like lung cancer and heart disease. These facts make smoking in a confined area a very risky proposition, especially when one considers how easily it can be avoided.

Pests & Pets

Other sources of air pollution are the various life forms we unwillingly share our buildings with. These include pests, mold, bacteria, and plants. Cockroaches and dust mites, for instance, are not undesirable just because they are ugly and germ-ridden. They also leave behind allergens wherever they go. These allergens settle onto surfaces such as the floor or furniture. Although they do not stay floating in our indoor atmospheres for long, when we vacuum or dust, we stir these particles up and release them once again into the air, where we, or those we share our living or working space with, can inhale them. According to the American Lung Association, this debris can trigger allergic reactions and asthma attacks, and may even be responsible for causing asthma to develop among the very young.

Nor do air pollutants come only from unwelcome “guests” like mites and roaches. Unfortunately, pets too cause similar problems by leaving dander behind them. In fact, the ALA points out, many of the harmful substances released by dogs and cats are lighter in weight than those released by the pests discussed above. This means that they are constantly floating in the air and do not need to be stirred up by human activity. Inhaling this matter can cause irritation of the respiratory system, rashes, and lung damage.

Poor Ventilation

As might be expected, poor ventilation and filtration will greatly exacerbate the pollution caused by indoor air pollutants by trapping them inside. A poorly ventilated fireplace, for example, or an air conditioning unit whose owner does not regularly replace its filter as directed by the manufacturer, can become seriously detrimental to the air quality of a home. The air inside will become saturated with chemicals, such as carbon monoxide or nitrogen dioxide, that can irritate the eyes or throat, and that are capable of causing serious health problems, including bronchitis and lung cancer.

Outdoor Pollutants Entering the Home

So far we have discussed common causes of indoor air pollution that originate from within the building itself. On top of these indoor sources, however, outdoor air pollutants can easily find their way inside as well. Most of the usual outdoor air pollutants can end up causing pollution indoors as well. Outside air will infiltrate an enclosed space through many avenues: open doors and windows are obvious examples, but even small cracks in walls, floors, and ceilings let outside substances in. Fans and other ventilation systems stir up the air, which moves from room to room as well as from the outside in.

These are only some of the more common causes of indoor air pollution. Some of them, such as smoking, can be remedied through simple means, but others are best combated through the use of an air purifier, which removes toxins from the air before they reach your lungs.

Summary of Indoor Air Quality Problems

• Fireplaces
• Gas ovens & stoves
• Building materials (paint, asbestos, pressed wood, wet carpets, etc.)
• Cleaning products
• Personal grooming products (Hair sprays & other aerosols)
• Tobacco smoke
• Pests (cockroaches, dust mites, etc.)
• Mold
• Bacteria
• Plants
• Pets
• Heating & air conditioning units with dirty filters
• Pollen
• Smog

Can Air Purifiers Help With Indoor Air Pollution?

Air purifiers can help with some of these problems (i.e. pollen, some tobacco smoke, some airborne mold & bacteria particles) but are not a total solution.  Removing pollutants at the source wherever possible and giving your home proper ventilation are the best solutions.

Sources referred to in this article:

• American Lung Association. “Cockroaches and Pests.” http://www.lungusa.org/healthy-air/home/resources/cockroaches-and-pests.html
• —. “Pet Dander.” http://www.lungusa.org/healthy-air/home/resources/pet-dander-1.html
• —. “Secondhand Smoke.” http://www.lungusa.org/stop-smoking/about-smoking/health-effects/secondhand-smoke.html
• United States Consumer Product Safety Commission. “The Inside Story: A Guide to Indoor Air Quality.” http://www.cpsc.gov/cpscpub/pubs/450.html
• United States Environmental Protection Agency. “Indoor Air Quality.” http://www.epa.gov/iaq/index.html
• —. “Respirable Particles.” http://www.epa.gov/iaq/rpart.html
• —. “Sources of Combustion Products.” http://www.epa.gov/iaq/combust.html
• —. “Smoke Free Homes and Cars Program.” http://www.epa.gov/smokefree/index.html
• World Health Organization. “Indoor Air Pollution.” http://www.who.int/indoorair/en/

The Ionic Breeze Air Purifier is popular for its effectiveness in purifying indoor air.
I recommend considering the Ionic Breeze PURIFY 9 Air Cleaner model.
It has gained a reputation for exceptional performance and advanced features.
For a comprehensive review of the Ionic Breeze PURIFY 9 Air Cleaner.
In summary, the Ionic Breeze PURIFY 9 Air Cleaner is an excellent choice for air purification.

A History

Some people who are considering purchasing an air purifier for their homes may have heard about Ionic Breeze, which for a time was a very big name in the world of home air purifiers. This article will examine what the Ionic Breeze was and what happened to it.

What was Ionic Breeze?

Ionic Breeze was a product of The Sharper Image, a brand specializing in high-tech products which at its peak operated over 180 stores in the United States, alongside an extensive online presence. Possibly because this process seemed more high-tech or cutting-edge than traditional air filters, Ionic Breeze was a popular filter for a time, and sold more than two million units.

The First Consumer Reports Article and the Resulting Lawsuit

Unfortunately, the hype surrounding Ionic Breeze failed to live up to the facts, and this proved to be not only a frustrating experience for those who purchased one, but also the downfall of its maker, The Sharper Image.

The controversy began in the year 2003, when Consumer Reports, a magazine dedicated to testing and evaluating consumer products, released a report on air filters that doubting Ionic Breeze’s claims to purify the air. The report found that ionic air filters such as the Ionic Breeze have a low Clean Air Delivery Rate when compared to traditional HEPA filters. HEPA (high efficiency particulate air) filters trap airborne particles in a fiber mat, and have been in use for many decades.

Not surprisingly, The Sharper Image was angered by the Consumer Reports article. They sued the magazine’s publisher, Consumer’s Union, claiming that the methods used for testing in the article did not give an accurate picture of the Ionic Breeze’s effectiveness. The lawsuit was ultimately dismissed, however, and The Sharper Image was forced to pay over half a million dollars to cover the legal fees of Consumer’s Union.

Further Consumer Reports Articles and the End of The Sharper Image

This was not the end of the negative publicity for the Ionic Breeze. Consumer Reports issued a second article in 2005 that was even more damaging than the first. Not only did the Ionic Breeze (as well as other ionic air purifiers) fail to significantly improve indoor air quality, it also released trace amounts of ozone into the air. Although The Sharper Image attempted to deny the report’s accuracy, it was generally accepted, and sales never recovered.

The magazine later also issued a report denying the value of the “seals of approval” given to filters such as the ionic breeze. And when The Sharper Image announced a new “OzoneGuard” attachment to reduce the amount of ozone released by the its signature air filter, Consumer Reports panned the device as ineffective.

A class-action lawsuit soon arose against The Sharper Image in response to these revelations. By 2008, the company went bankrupt, and it closed down all its stores by the end of that year. The company’s name is now used as a product brand that is sold via an online store and through various home-and-office style retailers.

What Ozone Is and Why It Is Dangerous

Most people, even if they do not know what ozone is, have heard of it, usually in context of the ozone layer in the atmosphere that protects the earth from ultraviolet light. However, ozone is not so benevolent a substance when we come into close contact with it. As the Environmental Protection Agency says: “Good Up High, Bad Nearby.”

Ozone is a molecule consisting of three oxygen atoms, rather than the two that comprise a “normal” oxygen molecule. The third atom can relatively easily become detached from the other two, and once free, it will interact with other substances. One of these “other substances” is your body. According to the EPA small amouts of ozone

“can cause chest pain, coughing, shortness of breath, and throat irritation”

as well as even worse effects.

In other words, those who purchase ozone-generating air purifiers to improve their indoor air quality may discover that the “solution” is worse than the problem. For instance, one Ionic Breeze owner interviewed by Consumer Reports claimed to have experienced a “dramatic reduction” in her asthma symptoms a mere two days after she turned off the device.

Conclusion

Although the Ionic Breeze initially had great appeal, eventually its design flaws were exposed. The story of its rise and fall can serve as a lesson to those looking for air purifiers to be aware of what they are buying. Especially, they should stay away from any “purifier” that releases ozone into the air. Indoor air pollution is a big enough problem without adding another harmful toxin into the mix.

Sources referred to in this article:

• Consumer Affairs. “Ionic Breeze Suit Drives Sharper Image into Bankruptcy.” http://www.consumeraffairs.com/news04/2008/02/sharper_image.html
• Consumer Reports. “Air Cleaners: The Truth Behind the Accolades.” http://www.consumerreports.org/cro/appliances/heating-cooling-and-air/air-cleaners/ionizing-air-cleaners-air-cleaners-the-truth-behind-the-accolades-505/index.htm
• — . “Proposed Settlement in Sharper Image Air Purifiers Case.” http://www.consumerreports.org/cro/home-garden/news/2007/02/settlement-in-sharper-image-ionic-breeze-class-action-2-07/overview/0702_sharper-image.htm
• Huffman, Mark (Consumer Affairs). “Ionic Breeze Suit Drives Sharper Image into Bankruptcy.” http://www.consumeraffairs.com/news04/2008/02/sharper_image.html
• Maxwell, Bud (eHow.com). “Ionic Breeze Air Purifier Problems.” http://www.ehow.com/about_5569141_ionic-breeze-air-purifier-problems.html
• MSNBC. “Consumer Reports calls air purifier ‘unhealthy.'” http://www.msnbc.msn.com/id/7391185/
• United States Environmental Protection Agency. “Ozone Generators that Are Sold as Air Cleaners.” https://www.epa.gov/indoor-air-quality-iaq/ozone-generators-are-sold-air-cleaners
• Wikipedia. “Air Ioniser.” http://en.wikipedia.org/wiki/Air_ioniser
• — . “HEPA.” http://en.wikipedia.org/wiki/HEPA
• — . “The Sharper Image.” http://en.wikipedia.org/wiki/The_Sharper_Image

Master Resource List

We’ve put together a list of air purification and indoor air quality (IAQ) resources for use by students, researchers, academic professionals, industry experts, and media. Our list covers a variety of topics from technology to health to scientific research and will be updated regularly. Please contact us if you feel an important consumer focused resource is missing from our list. (Updated February 3, 2011)

Air Purification General

• Environmental Protection Agency (EPA): Residential Air Cleaning Devices (2nd Edition) – An August 2009 update to the EPA’s original guide to air cleaning devices in the home.  This essential document outlines common air pollutants, types of air cleaners, measuring air cleaner efficiency against common pollutants, and the health impact of air cleaners.  This document should be the starting point for any interested in the main issues surrounding residential air purification.
• Association of Home Appliance Manufacturers (AHAM): Clean Air Delivery Rate – Although a pro-industry group, AHAM has succeeded in forming an ANSI-certified standard for measuring air purifiers called the Clean Air Delivery Rate (CADR).  This site explains what the rating means for consumers and manufacturers and also lists which air purification companies participate in the program and what CADR their products received for tobacco, pollen, and smoke, the main pollutants CADR measures.
• EPA: Ozone Generators Sold As Air Cleaners – The EPA examines the health risks of ozone generating air purifiers and how ozone impacts health.
• EnergyStar Approved Air Cleaners (PDF) – Most recent list of U.S. Department of Energy “EnergyStar” rated air cleaners.  Also listed are standards used for the EnergyStar rating and a savings calculator (XLS file) for consumers to find out real savings from EnergyStar approved air cleaners.
• California Environmental Protection Agency: Particles and Air Cleaners – The State of California’s guide to air cleaner products including Fact Sheets on reducing exposure to particle pollutants, FAQ on air cleaning devices for the home, and air cleaners to avoid. 
• ______: Hazardous Ozone-Generating “Air Purifiers” – Another guide from the State of California regarding the hazardous production of ozone by some air purifiers.  Includes a list of California certified air cleaners, research reports, and press releases.
• Health Canada: Ozone Generator Q&A – Health Canada, a Canadian governmental agency, lists important questions regarding ozone generating air purifiers along with answers which including regulations, studies, consumer complaints.
• National Air Filtration Association – Trade association for the air filtration industry.  Members are individuals and companies that sell, service and manufacture air filtration products all over the world.  Membership is also extended to those who are members of other organizations like the Indoor Air Quality Association (IAQA), American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) and others.
• Texas A&M: A Strategy For Reducing Pollutants In Indoor Air? – Guide detailing ways home owners can help keep indoor air clean in addition to air filtering products

Health Issues Related to Indoor Air Quality

• California EPA: Sources and Potential Health Effects of Indoor Air Pollutants – Fact sheet that identifies potential indoor air pollutants along with potential health effects
• California EPA: Reducing Your Exposure to Particle Pollutants (PDF) – Guide to identifying and limiting exposure to harmful particle pollutants, an alternative to air filtering
• California EPA: Combustion Pollutants In Your Home – How to recognize sources of indoor pollutants, health effects, and what home owners can do to eliminate these sources without air filtering
• California EPA: Combustion Pollutants In Your Home 2 (PDF – Addendum to original report) – May 1994 update to the original report that presents more current findings
• State of California Certified Air Cleaning Devices – Air cleaners that have been approved for sale by the State of California due to meeting stringent ozone requirements.
• California EPA: Cleaning Products and Indoor Air Quality – Guide to understanding how some cleaning products may contribute to indoor air pollution.
• The New England Journal of Medicine: Environmental Intervention and Asthma – NEJM study on what the impact of cleaning up the environment has on asthma sufferers.
• EPA: Will Air Cleaning Reduce Effects From Indoor Air Pollution? – Subsection of the EPA’s 2nd Edition on residential air cleaners addresses the effectivenes of these products on reducing negative health symptoms.
• WebMD: Asthma and Air Filters – WebMD opinion on the effectiveness air purifiers have on asthma symptoms.
• Asthma and Allergy Foundation: Air Filters – Discusses issues surrounding air filtration and allergy relief
• EPA/AirNow: Particle Pollution and Your Health – How particles in the air affect your health and how to manage exposure.
• How to Decide If Your Office Needs an Air Purifier – Guide to determining workplace related illness linked to poor indoor air quality and how air purifiers can help.

Air Purifier Performance

• Consumer Reports 2010 Findings (Subscription Required) – Consumer Reports releases findings on the efficiency of some air purifers about every 3 years.  Testing is based on smoke, pollen, and dust removal.  Consumer Reports does not give detailed information on their testing methodology.  Most recent air purifier test was done in their September 2010 issue (always available online) but only gave test results for 20 portable models, 2 professionally installed HVAC systems, and 5 consumer installable furnace filters.
• Consumer Reports 2007 Findings (PDF) – 2007 edition of Consumer Reports air purifier ratings made freely available to the public.
• Consumer Reports 2005 Findings (PDF) – 2005 edition of Consumer Reports air purifier ratings made freely available to the public.
• Air Purifier Clean Air Delivery Rates – Certified tests of select air purifiers and how they perform in the removal of smoke, pollen, and dust
• British Allergy Foundation: Seal of Approval (Air Purifiers) – The non-profit British Allergy Foundation has recognized select air purification products which “restrict/reduce/remove allergens from the environment of the allergy sufferer and for products which have significantly reduced allergen content.”  No guidelines are given concerning the degree to which these products restrict, reduce, or remove allergens.

Indoor Air Quality (General)

• Environmental Protection Agency: Indoor Air Quality – EPA’s main IAQ portal addressing issues like asthma, mold & moisture control, radon, education for home buyers, and an interactive tour of a home and standard indoor air quality issues home owners face.
• Indoor Air Quality Association – A non-profit organization established in 1995 that serves as an information exchange between professionals along with a public facing educational resource.  IAQA also offers certified courses from industry professionals and academic leaders in the IAQ industry.
• Occupational Health & Safety Administration (OSHA): Indoor Air Quality – Information about air quality issues in the workplace including how hazards are recognized, evaluation and control of IAQ issues, and other resources.
• Consumer Product Safety Commission (CPSC): Indoor Air Quality Publications – Safety alerts and guides to consumer products that have an affect on indoor air quality including paint strippers, biological pollutants, carpet, lead, asbestos, and much more. 
• US National Library of Medicine and National Institutes of Health: Indoor Air Pollution – A master resource list like this one covering a broad range of indoor air pollution topics from basics to organizations to important journal articles.
• Centers for Disease Control and Prevention: Indoor Environmental Quality – Lists health evaluation reports from the National Institute for Occupational Safety and Health (NIOSH) researching potential hazards in the workplace.  These reports outline how NIOSH responds to complaints and how they test and evaluate potentially contaminated areas.
• State of California Indoor Air Quality Program – The State of California has been a forerunner in addressing indoor air quality issues, especially the evaluation of air purification products.  This site lists common indoor pollutants, how to address those pollutations, and how to find an IAQ professional.
• American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE): The Indoor Air Quality Guide – Best Practices – ASHRAE advances HVAC issues through research, standards, and continuing education.  This guide addresses for building design, construction, & maintainability of IAQ systems.
• Florida Department of Health: Indoor Air Quality – State of Florida program to help educate and reduce exposure to indoor air contaminants by the general public. 

Legal Issues

• California Air Cleaner Regulation – September 2007 regulation adopted by the State of California to prohibit the sale of air cleaners that release potentially harmful amounts of ozone as part of the air purifying process.

Portable Air Purifier Manufacturers & Brands

• 3M Filtrete
• Aerus
• Air-O-Swiss
• Aireox
• Airfree
• Airgle
• Airpura
• Alen
• AllerAir
• AmairCare
• Austin Air
• Bionaire
• Biotech Research
• Blueair
• Continental Fan (CFM)
• Coway
• Dr. Caboodle
• FilterQueen
• Friedrich
• Funglan
• Germ Guardian
• Hamilton Beach
• Holmes
• Honeywell
• Ion Flow (Sharper Image)
• Ionic Pro
• IQAir
• Kenmore
• LG
• NeoAir
• NQ Industries
• Oransi
• Oreck
• Panasonic
• Pure Air Systems
• Rabbit Air
• Sharp
• Swizz Style
• Tiger Corporation
• Ultra Sun Technologies
• Vollara
• Vornado
• Westinghouse HVAC
• Whirlpool
• Winix
• Zojirushi

Industrial and Commercial Air Filtration Manufacturers

• AirFlow – Provides filtration for commercial and industrial HVAC systems.
• Cameron Great Lakes Inc. – Specializing in molecular filtration media.
• Clarcor – Product lines include air filters, antimicrobial filters, dust collection systems and filters, electrostatic air filtration, carbon filters, paint overspray filters, HEPA filters, and air pollution control systems.  Owns Airguard, Air Technologies Inc., and Purlator brands.
• Columbus Industries Inc. – Global provide of a broad range of filtration products.
• D-Mark Inc – Specializing in activated carbon filtration for odor, gas, and particulate removal.
• Flanders – Designs, manufactures, markets, and distributes air filters for commercial and residential heating, HVAC systems, semiconductor manufacturing, ultra-pure materials, chemical, biological, radiological and material processing, biotechnology, pharmaceuticals, synthetics, nuclear power and nuclear materials processing.
• Glasfloss Industries – Oldest manufacturer of HVAC filters for commercial, residential, and industrial applications.
• Koch Filter Corporation – Produces air filtration products for commercial, industrial, hospital, gas turbine, and paint filtration applications

Questions?

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Allergies and Airborne Particles

It is necessary to do some research to determine which product is best suited for the kind of allergens that cause the irritation, because not all units produce the same results.

Sources of Indoor Allergy Triggers & Effectiveness of Air Purifiers

According to the Asthma and Allergy Foundation of America (AAFA), a non-profit patient advocacy group

If these particles stay suspended in the air, some air purifiers can filter them.  However, pet dander and dust mite feces in particular are heavier particles that often settle quickly and do not stay suspended in the air for long.  Air purifiers are effective at removing tobacco smoke but the best recommendation is not to allow smoking in the house at all.

Strategies For Reducing Indoor Allergy Triggers In Addition to an Air Purifier

The United States Environmental Protection Agency (EPA) does recommend air purification products as part of the solution to tackling indoor air pollution that causes allergies, but considers it just part of a overall strategy that includes:

• Adequate ventilation
• Removal of on-going pollution sources like pets, smoke and mildew
• Replacement of materials that emit VOCs
• Air purification devices either for single rooms or whole house systems

Of course, many allergy suffers are affected seasonally by pollens and other environmental factors. In this case, the correct type of air purification device can prove very beneficial since these irritants are typically large particles that can easily be trapped by a filter.

Air Purifier Filter Technology

Air purification technology uses a number of different methods for air filtration, and it is recommended by the AAFA that you consult with your doctor to determine which type of system will eliminate the specific allergens that trigger your symptoms. AAFA cautions consumers about accepting the manufacturer’s claims and urge them to investigate the pros and cons of different methods fr themselves with their doctor’s guidence. The following air purification products are the most common for residential use:

• HEPA Filters – and must be replaced every 6 months to a year and are typcially effective for seasonal allergies. 
• Electrostatic Filters – May produce small amounts of ozone so these are rarely recommended.
• Hybrid Filters – Using barrier filters like HEPA and material such as activated carbon to filter gasses provides an effective combination to reduce some types of allergen triggers
• Ozone Generators –

For maximum protection, whole house air purification systems installed as part of the HVAC unit are highly recommended to filter larger particles combined with portable units with HEPA filtration to filter the smallest particles in rooms where allergy sufferers sleep.

Air Purifier Feature Considerations

Once you have determined the correct type of air purification system that works best for your particular allergies, you also need to consider the following factors before purchasing:

• Coverage area –
• Noise level –
• Cost and ease of filter change –
• Efficiency rating –  

For Further Information:

WebMD on Air Filters – http://www.webmd.com/asthma/guide/do-you-need-an-air-filter Allergy and Asthma Foundation of America – http://www.aafa.org/ Mayo Clinic (Asthma Friendly Products) – http://www.mayoclinic.com/health/asthma-friendly/AS00033/NSECTIONGROUP=2

 

Can an air purifier help with asthma?  Experts weigh in.

Asthma sufferers are always interested in finding new ways to remove the particles in the air that aggravate their condition, and air purifiers certainly seem like a good solution to the problem and are often recommended by doctors. However, many studies by the EPA, Indoor Air Research facilities at major universities, and the American Lung Association have shown that this is not necessarily the case, although many air purification products advertise that they are effective in reducing asthma causing airborne contaminants. While this is true to a degree, studies show that residential air purification units — especially portable ones — have a limited effect.

Independent Studies

Research reported in the New England Journal of Medicine in 2004 showed that adding an air purifier to an urban home with children who suffer from asthma did create an overall better environment, but did not totally alleviate their asthma symptoms entirely since many of the irritating factors– especially dust mites and pet dander — are stirred up by sitting on furniture, walking across carpet or laying down on a pillow, and air purifiers cannot remove them from the room until they reach the filtration mechanism.

It is recommended that the source of allergens needs to be eliminated from indoor environments before an air filter can make a substantial difference. Obvious suspects like shedding pets, outdoor dust infiltration, cigarette smoke and mold and mildew buildup must be addressed directly and it is not realistic to expect residential air purification products to thoroughly overcome such contaminants to a degree that it would eliminate the cause of asthma attacks.

Federal Testing

Environmental Protection Agency (EPA) studies have found that many of the airborne particulates that cause asthma are not filtered out because they are too small — under 0.3 microns — and that although residential air purifiers consistently decrease indoor concentrations of airborne irritants by 80%, which is an improvement, but should not be considered a definitive solution.

Ozone is Dangerous to Lung Health

The EPA actually warns consumers — especially asthma sufferers — about the dangers of air purifiers that emit ozone, claiming that short term or extended exposure to ozone can actually increase asthma symptoms because it is has toxicological properties that restrict and hamper lung function, even in healthy people. They do point out that there are no definitive studies on gas-phase filtration systems, photo catalytic oxidation cleaners (PCO) systems or UVGI (ultraviolet) systems, but express doubt that they are any more effective in reducing the tiny airborne particulates that most irritate asthma symptoms.

Medical Observations

Another important observation is discussed on the WebMD website that examines the effectiveness of indoor air cleaners. The article points out that portable room cleaners only work in the room in which they are running, so they should be located in strategic areas where the asthma sufferer spends most of the time, and especially in the bedroom at night. It recommends HEPA filters as the most effective for removing asthma causing particulates from the air, but admits that their effectiveness is limited.

Conclusion

• New England Journal of Medicine – adding an air purifier helped air quality but didn’t totally alleviate asthma symptoms due to allergens & asthma triggers still located on surfaces and not in the air

• Environmental Protection Agency – air purifiers reduced particles in the air considerably but did not filter allergy and asthma triggering particles smaller than .3 microns

• WebMD Asthma Guide – HEPA filter based air purifiers helped clean the air but effect on asthma symptoms limited

Bottom line – Air purifiers can help clear the air considerably of many (not all) asthma inducing particles and irritants but are only a partial solution for asthma sufferers.  Surfaces that contain irritants need to be cleaned regularly and sources of irritants should be removed wherever possible.

Strategies Recommended By the Environmental Protection Agency (EPA)

When the dangers associated with indoor air pollution are considered, the importance of keeping the air in your home as pure as possible becomes obvious. Fortunately, there are a few relatively easy steps that you can take which will result in a noticeable improvement in your home’s air quality.

The Environmental Protection Agency recommends a three-prong method of reducing indoor air pollution: source control, improved ventilation, and air cleaners. Let us look at each of these three methods in turn.

1 – Source Control

Sometimes the best way to deal with pollution is to cut it off at the source. Some sources are fairly easy to reduce or eliminate.

Perhaps the quintessential example of source control is cutting down on environmental tobacco smoke, also known as “second-hand smoke.” If you do not want to quit smoking, you can still decide to only smoke outside, and to ask those you live with and your guests to do the same. That way, you are not continuously inhaling the unhealthy by-products of smoking.

Here are some other methods of source control:

• Have your air tested for radon, which, after smoking, is the leading cause of lung cancer. If it turns out you have a radon problem, address it as soon as possible.

• Fight mold, mildew, and pollution-causing pests such as cockroaches and dust mites by keeping the humidity of your home low. It is also import to keep your living space clean so that it is less attractive to bugs. If you do have pests, try eliminating them using non-chemical means rather than sprays.

• Make sure that furnaces, chimneys, and other heating systems are running cleanly and efficiently.

• When cleaning, check for any warnings on the label. If it says not to use the product in an enclosed space, don’t do so. Buy only the quantities you need so that you do not have unnecessary and unhealthy chemicals sitting around your home.

• Use furniture made of solid wood, rather than pressed wood, which can release formaldehyde into the air.

2 – Improved Ventilation

Throw open the windows the next time there is good weather.

Sometimes you will need to immediately increase ventilation. We mentioned above, for instance, that it is preferable to use non-chemical means to combat household pests. However, if you do need to use insect spray, immediately open the nearest window and turn on the fan if at all possible, so that the unhealthy fumes do not stay in your house. The same goes for other chemicals, like cleaning fluids.

3 – Air Purifiers

Effectiveness of Air Cleaners

The effectiveness of air purifiers vary from model to model. Both the EPA and the USCPS say that the value of a filter should be measured based on two factors:

How much air it is capable of drawing through the filtration system.

Efficiency is usually measured as a percentage. The higher the percentage, the more unwanted material the filter pulls from the air that goes through it. The second factor, airflow rate, is measured in cubic feet per minute. This is probably the more important factor to remember, because while it is obvious that the higher the efficiency, the better, the smart buyer will consider his or her needs when it comes to airflow rate. The air volume of a room can be measured by multiplying three numbers: the length and width of the floor and the height of the ceiling.

Conclusion

Air filters, like source control and improved ventilation, are not cure-alls, nor are they an excuse to avoid taking other measures to purify the air of your home as described above. The filters used in homes are usually those that focus on removing particles from the air. Other types of filters exist, but are not nearly as common. Ozone-generating air cleaners are also available on the market, but are not recommended, as ozone itself is a health hazard. Standard particle-removing air filters are most effective against small particles. Larger particles tend to stay in the air for shorter periods of time before settling onto the floor or some other surface. They may be stirred up again by human activity, but gravity will soon pull them down once more. Therefore, air filters are less capable of ridding them from your home than smaller particles.

Please note also that air filters are currently not recommended by the EPA to control radon or its decay products, though more research is being planned in this area.

Despite these caveats, however, air filters can work wonders for indoor air quality, and can leave your home significantly cleaner than it was without one, no matter what other steps you take. Air filters are therefore an important component in improving the air quality of your house or apartment.

Sources referred to in this article:

• American Cancer Society. “Secondhand Smoke.” http://www.cancer.org/Cancer/CancerCauses/TobaccoCancer/secondhand-smoke
• United States Consumer Product Safety Commission. “Improving Air Quality in Your Home: Three Basic Strategies.” http://www.cpsc.gov/cpscpub/pubs/450.html#Improve5
• United States Environmental Protection Agency. “Improving Indoor Air Quality.” http://www.epa.gov/iaq/is-imprv.html
• —. “Indoor Air Quality.” http://www.epa.gov/iaq/is-apart.html
• —. “The Inside Story: A Guide to Indoor Air Quality.” http://www.epa.gov/iaq/pubs/insidest.html