Pets and People

Pet Allergies: Filtering Air

posted: 05/15/12
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According to the American College of Allergy, Asthma & Immunology, animal allergies affect about 10 percent of the total U.S. population. But don't let the numbers fool you: Despite the potential for symptoms like sneezing, skin rashes and even asthma, a lot of allergy-prone people still own pets. Many who are in this boat turn to products like air filters to help them breathe easier in the company of their furry friends. But can these purifiers really get the job done, or are they nothing more than a lot of hot air?

Allergen Origins

First things first: It's important to understand where pet allergens come from, because contrary to popular belief, they don't originate in pets' hair, fur or feathers. Pet allergens are actually proteins secreted through animals' saliva, urine and skin glands, which dry on dead skin and shed off as dander. Once airborne, the tiny flakes can land on household items and surfaces, including furniture, bedding, carpets, walls and drapes.

Catching these allergens without specialized filters can be difficult, mostly because they're so small. The unit of measure for air particles is the micron, which equates to 1/25,400 of an inch, and most regular room air conditioners can grab only particles that are 10 microns or larger. Anything smaller than 10 microns -- including pollen, dust, mold and pet dander -- is not visible to the naked eye. Pet dander in particular is among the tiniest of these small particles, which means it may linger in the air longer before settling.

Filtration Basics

There are two main technologies used to remove unwanted particles, including allergens, from the air. The first is a mechanical system that captures them on filters. High Efficiency Particulate Air (HEPA) filters fall into this category -- they're popular with people who have pet allergies, because they have fine sieves and can catch many small allergens. However, HEPA filters can be costly, because they need to be replaced periodically, depending on how often you use them.

Alternatively, some opt for electronic air filtering systems, which operate on an electrostatic technology. They work by drawing air through an ionization section, where the allergens receive an electrical charge. The charged particles are then either collected on flat plates, or if you're using an ion generator, released into the air, where their charge helps them quickly attach to other particles and settle onto surfaces. The downside of the latter scenario is that you have to follow up and clean any area where the ionized allergens could have landed (which could be pretty much anywhere, including the walls or floor). The other downside of all electrostatic-based systems is they create ozone gas, which can be toxic in large quantities, but damaging to the lungs even in small amounts.

The Bottom Line

Both types of technology are available as portable units or more comprehensive filters that you can add to furnaces or the central heating and cooling system of your home. Also, certain cleaning tools, such as handheld and upright vacuums, may come already equipped with special filtration systems. Depending on the type of system you choose, air filters can cost anywhere from less than $100 to more than $1,000, but according to a study done by Consumer Search, a higher price tag doesn't necessarily equal better quality when it comes to these products. Ultimately, the specific air filter model you end up getting may depend a great deal on the amount of dander you're trying to rein in.

All that still leaves you with the million dollar question: Are these air filters any good at tackling pet allergens in your home? The answer is both "yes" and "no." Typical air cleaners impact only particles that are still airborne, so they don't do much in terms of eliminating dander that's already landed and nestled into fabrics, carpets, walls and other surfaces. However, while it still won't eliminate allergens entirely, a filter used in conjunction with regular household cleaning can be a good one-two punch to further decrease the overall amount of dander in the home. This combined approach is also one where investing in something like a HEPA filter-equipped vacuum can play an important role, since it may give household chores an extra boost and go a long way toward keeping allergy symptoms at bay -- and helping you enjoy time spent with your pet.


American College of Allergy, Asthma, & Immunology. "Advice from Your Allergist: Pet Allergies." 04/08/2010.

Asthma and Allergy Foundation of America. "Indoor Air Quality and Allergens." 04/13/2010.⊂=18&cont=233

Consumer Search. "Air Purifiers: Full Report." 01/01/2010.

Environmental Protection Agency. "Guide to Air Cleaners in the Home."

Schnurnberger, Lynn. "Shed Your Pet Allergies Now." PARADE Magazine. 04/08/2010.

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