The promise of an air purifier is an enticing one: An appliance designed to cleanse the air in your home, getting rid of all the impurities including odors, smoke, dust, and pet dander. Given the fact that indoor air can have levels of certain pollutants up to tive times higher than outdoor air, we get it. But in reality, not all air purifiers necessarily live up to the marketing hype.
How do air purifiers work?
Air purifiers usually consist of a filter, or multiple filters, and a fan that sucks in and circulates air. As air moves through the filter, pollutants and particles are captured and the clean air is pushed back ot into the living space. Typically, filters are made of paper, fiber (often fiberglass), or mesh, and require regular replacement to maintain efficiency.
That means, in addition to the purchase price of an air purifier, you should also factor in operating costs and filter replacement costs. Operational costs can easily amount to $50 annually, since you should be running air purifiers near constantly to garner the benefits. Filter replacements can run upwards of $100 a year all told.
Other air purifiers use ionizers to help attract particles like static — negative ions bond to dust and allergens and make them settle out of the air. If you're intersted in buying an air cleaner that uses ionizers, make sure it does not produce ozone. , a gas made up of three oxygen atoms that is often marketed as helping break down pollutants, because ozone could be a lung irritant and further aggravate asthma conditions. Usually the air purifiers with ozone will have that listed on packaging or in the marketing descriptions.
What are air purifiers supposed to filter out — and do they actually do it?
Most filters on the market are designed to capture particles like dust and pollen, but don't catch gases like VOCs( volatile organic compounds) or radon.That would require an adsorbent, like activated carbon. In fact, the Environmental Protection Agency (EPA) warns that the functionality of air purifiers is limited in terms of filtering out gases, and that you must frequently replace filters for optimal functionality, usually about every three or so months.
So while many air purifiers are good at filtering pollutant particles out of the air (dust, smoke, pollen, etc.), they are not necessarily very good at removing gaseous pollutants like VOCs or radon from the air that may accumulate from adhesives, paints, or cleaning products. Allergens that are embedded into furniture or flooring are also not captured by them.
If you are concerned about mold, we’d recommend buying a dehumidifier or humidifer to help maintain the appropriate moisture levels in your home and stave off mold growth issues. Air purifiers do not prevent mold growth, so it is necessary to eliminate the source of moisture that is allowing it to grow.
So… should I buy an air purifier?
Before you do, know that air purifiers are not a cure-all. There is very little medical evidence to support that air purifiers directly help improve your health or allerviate allergies and respiratory symptoms.That’s due in part to the fact that it is very difficult to separate the effects of known air-quality pollutants in your home from other environmental and genetic factors. (For instance, how are the furnishings and ventilation in your home affecting you in addition to any indoor pollutants?) But if you are an allergy or asthma sufferer, an air purifier with a HEPA filter may be helpful for you as it will be good at removing fine airborne particles.