Breathe Easier with Whole-House Air Purification
According to the Environmental Protection Agency, the air inside our homes may be anywhere from 2-5 times as polluted as the great outdoors. Today's tightly sealed, energy-saving construction has actually made this problem worse. Air leaks are reduced, which improves HVAC performance admirably, but the decrease in ventilation leaves airborne allergens and other contaminants trapped inside. The result? Your home's air quality suffers, as does your health. Whole-house air purification systems combat this problem and help you breathe easier by cleaning the indoor air.
What Whole-House Air Purification Systems Can and Cannot Do
Whole-house air purification systems provide relief for family members with allergic rhinitis or asthma. These purification systems are designed to remove allergens, including pollen, dust, dust mites, and animal dander, from the indoor air. Some will also filter out cigarette smoke and certain harmful VOCs (volatile organic compounds), chemicals which may be off-gassed from common household items such fresh paint or synthetic fabrics and flooring. All of them are capable of removing only airborne contaminants, however, and not toxic substances which have settled on a surface.
Don't expect the systems to remove all toxicity from your home's air, either. For healthier indoor air, you should also implement practical measures yourself. Ask smokers to indulge out of doors. Avoid storage of toxic substances like paint, pesticides, or solvents inside the house. Be sure that fuel combustion appliances (kerosene heaters or gas stoves, for instance) are adequately vented and never use gas or charcoal barbecues or camping stoves indoors. Install a carbon monoxide detector and have your house checked for the presence of mold or radon.
How the Systems Work
If your home utilizes forced-air HVAC, an efficient whole-house air purification system can be built in, using the ductwork and blower which are already in place. Make sure that the air filtration system you purchase will not interfere with the efficient delivery of heating and cooling. You will also need to scrupulously clean the ductwork before installation and keep it clean. There are a few non-ducted air purification systems which may be freestanding or wall-mounted; they tend to be on the pricier side.
The advantage of a whole-house purification system over smaller, portable versions is that it is extremely powerful and affects all rooms of the home, yet it has a much quieter fan. However, this type of system is also quite expensive and usually must be installed by an HVAC professional. The best-selling models cost approximately $2500-4000, not including installation.
What to Look for
When purchasing a whole-house system, you will find various types of air cleaning mechanisms to choose from. An HEPA filter is a barrier that will screen out airborne allergen particles as small as 0.3 microns. A hybrid filter combines a barrier method with another substance (usually activated carbon) to filter out tobacco smoke as well as allergens. An electrostatic precipitator utilizes an electric charge to attract and collect allergens in the air; however, its electrostatic plates demand frequent cleaning and the system may produce a small quantity of ozone. An ozone generator works to eliminate airborne contaminants, but its high level of ozone is dangerous for people with breathing problems.
ASHRAE (the American Society of Heating, Refrigerating, and Air-Conditioning Engineers) rates whole-house air purification systems on a scale from 1 to 16, according to their MERV (minimum efficiency reporting value). Consumer Reports found that the best-performing filter systems they tested tended to have a MERV rating of 10 or above.
Finally, compare the various whole-house air purifications systems based on the cost of replacement filters and the length of their warranties.
Laura Firszt writes for networx.com.