BookmarkAll About Home Air Purifier Filters
A breath of fresh air for your home
Home air purifiers remove dust, allergens, pet dander, toxins, mold and other particulate matter by forcing air through a filter and then returning the cleaned air to the room. The Environmental Protection Agency warns that indoor air is generally two to five times as polluted as outdoor air. Although sufferers of respiratory ailments like asthma and emphysema have a particular interest in air purification, dust, pollen, bacteria and other airborne pollutants can adversely affect the well being of otherwise healthy people.
Though exposure reduction and ventilation can best eliminate foul odors and pathogenic gasses, home air purifiers can reduce the levels of dust, dander, spores, smoke and other breathable particulates in the air. Self-contained, tabletop or room-size appliances that serve smaller areas are most common, though larger systems can attach to a forced-air furnace or central air conditioning unit to clean the air cycled through the system.
Why buy a home air purifier
How clean is clean?
As much time as we spend washing dishes, doing laundry, and scrubbing floors, it's easy to overlook another source of unhealthy dirt and unhygienic irritants: the air we breathe. The EPA ranks indoor pollution as one of the greatest environmental risks facing us today. In fact, the air we breathe inside our homes can be two to five times more polluted than the air outside.
While pollution from industrial sources, automobiles, and construction detracts greatly from the quality of our air, a number of sources of harmful fumes, vapors, and breathable particles lurk in the home, such as mold spores, dust, pollen, and tobacco smoke.
Although particularly bothersome to people who suffer from allergies, asthma, or emphysema, these irritants can produce complications in otherwise healthy people, particularly children and the elderly. Worse, most of these harmful substances are invisible, penetrating deep into the bloodstream through the lungs and accumulating inside the body, day after day.
Expert opinions
Many leading health agencies advocate the use of home air purifiers. The American Lung Association endorses the use of HEPA air filters in the bedrooms of people who suffer from asthma. The Asthma and Allergy Foundation of America, the Mayo Clinic, and the British Allergy Foundation also recommend home air purifier systems for people with respiratory ailments.
Lines of defense
The best way to avoid the negative health consequences of exposure to toxic or pathogenic fumes and particles is to reduce contact with these substances. The EPA and comparable state agencies maintain databases of air quality indexes and reported hotspots as a matter of public record to help people figure out where exposure is likely to take place.
The second line of defense is adequate ventilation. Opening a house to cleaner outside air can dilute the concentration of harmful chemicals inside. A home air purifier or air filtration system provides another important component in maintaining healthy conditions.
The technology of purity
Some air purification systems work in conjunction with other systems, such as a central air conditioning or heat pumps. These whole house air purifiers function mostly to clean the conditioned air of their systems, filtering out large particles, such as dust. Although beneficial, they may be expensive to install and fail to remove smaller particles from the air, such as bacteria.
Freestanding units, ideal for the filtration of the air in a single room, use different technologies to clean the air, targeting specific kinds of particles. Electronic air filters use electrostatic charge to target larger particles. UV (ultraviolet) filters, popular with hospitals and medical practices, treat the air with powerful rays of light, targeting viruses and bacteria. HEPA filters force air through a maze of filters, trapping even the tiniest particles. Some units combine technologies for maximum protection.
What kind of air purifier do I need?
Air traffic control
HEPA (High Efficiency Particle Absorbing) filters remove 99.97% of particles larger than three microns (a micron equals a one-millionth of a meter). Originally created during World War II to prevent leakage of radioactive particles from early nuclear reactor sites, these excellent filter systems maintain health and hygiene in businesses, hospitals, military installations, and private homes. A true HEPA system needs a great deal of air pressure to function, rendering them impractical for home usage. Most residential products are actually "HEPA-like" and provide approximately 90% to 95% effectiveness, depending on the manufacturer.
Ionic air purifiers operate not by forcing particles through a filtering medium, but by altering the electrostatic properties of the particles themselves. By negatively charging all the particles that come into contact with it, an ionic air purifier creates a strong attraction in these particles. These ions eventually draw positively charged matter to them like magnets, rendering them too heavy to float. The particles fall out of the air and end up collected on the floor or some other surface where they can easily be swept away or vacuumed.
Ultraviolet air treatment systems destroy airborne germs and mold spores with powerful rays of light. UV technology, employed for over a hundred years in hospitals and labs to destroy pathogens, has only recently become affordable enough for home use. Most effective at removing disease-causing agents from the air, these specialized machines do not treat air for smoke or other particles.
Some new systems combine these various forms of air filtration technology to minimize exposure to harmful agents in the air.
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