Do air purifiers work?
How many mentions of air purifiers have you seen recently? There are demos on TV, ads and articles about air purifiers in our magazines, and even celebrity endorsements. Has our indoor air gotten so bad that we need to think about air purifiers for our homes?
Yes, without a doubt. According to the United States Environmental Protection Agency, “Indoor air pollution is among the top five environmental health risks.
But how does our household air get contaminated in the first place? The answer, it turns out, is “very easily and very often”. Common contributors to indoor air contamination include:
Airborne particles, such as dust, smoke, pet dander, pollen, and particles circulated by cooking, and heating and air-conditioning systems. Contaminating particles also include tiny organisms such as bacteria, mold spores, dust mites, and viruses.
Gaseous pollutants from combustion processes, including gas cooking stoves, vehicle exhaust, and tobacco smoke.
Other sources include building materials, furnishings, and the use of products such as adhesives, paints, varnishes, flea removers, cleaning products, and pesticides.
Do air purifiers really eliminate them? Yes, they do. There are several kinds of air purifiers, each of which matches a kind of contaminant:
Particle removal. Mechanical air filters (often called HEPA filters) are designed to filter poor quality indoor air, removing the kinds of the particles previously listed.
Biological purifiers (UVGI, Ozone, PCO). These usually use ultraviolet (UV) light, particularly to kill bacteria and molds that are found on ducts. There is a potential problem with this kind of air purifier, however, because high levels of ozone emitted from use of ultraviolet have been found to have a negative effect on our health.
Gaseous pollutants removal. PCO cleaners work also by using UV lamps which can remove gaseous pollutants in the air. One of these gases, benzene, is said to reduce our red blood cell count and, thankfully, can be filtered out. Again, though, the use of UV usually creates ozone, damaging to your lungs in high concentrations.
There are many kinds of portable air cleaners available that have been designed to provide pure, clean air in the rooms in our homes or in small offices. Most of us are familiar with the air purifiers for entire buildings or warehouses and are part of the heating, ventilation, and air-conditioning (HVAC) system. These are not very practical for the home so free-standing air units are most often used.