Do you know what your air conditioning and heating system’s MERV ratings are, and how they can help protect your loved ones?
People often talk about outdoor air quality and how it affects our health — but did you know that poor indoor air quality can be just as detrimental? Poor indoor air quality can cause or contribute to the development of infections, lung cancer and chronic lung diseases, according to the American Lung Association.
“Mold, dust mites, insect feces and other particles in the air can trigger allergies and asthma attacks,” says Janice Nolen, assistant vice president of the American Lung Association in Washington, D.C.
If you want to improve indoor air quality, keep sources of pollution out of the home by ensuring you have good ventilation, both into and out of the house, Nolen explains. “A lot of mold, bacteria and other pollutants need moisture to grow. So keeping humidity levels below 50% and fixing leaks can help reduce risks,” she says.
What’s Your MERV Rating?
Another way homeowners can maintain healthy indoor air quality is by making sure their HVAC system (heating, ventilation and air conditioning) has filters with the recommended MERV (minimum efficiency reporting value), and that they are clean and operating effectively.
The MERV rating chart was designed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) in the ’80s to rate how efficiently a filter captures particles of different sizes. Every filter has a MERV rating that ranges from 1 (least efficient) to 16 (extremely efficient). Sears sells filters that go up to a high-efficiency MERV 13 rating. In fact, Sears PartsDirect has a program that can automatically ship filters to you, making it easy to remember to change them out every few months.
Choosing the right filter depends on your home and your goals. There are four categories of MERV filters to choose from.
Common disposable spun-fiber filters generally have a MERV rating of 1 to 4, and will not stop particles of less than 10 microns. They’ll catch pollen and dust mites but aren’t ideal for maintaining healthy indoor air quality.
MERV filters with a 5 to 8 rating will collect particles as small as 3 microns, such as mold and dusting aids, which is better for the typical homeowner.
Filters with a MERV rating of 9 to 12 are often used in commercial and industrial applications. These are a good choice for families with allergies or breathing-related illnesses or those who simply want the best dust control possible. They’ll filter out humidifier and lead dust and Legionella bacteria, which causes Legionnaires’ disease.
Filters with a MERV rating higher than 12 are the most efficient — stopping particles of less than 0.3 microns, including all bacteria and tobacco smoke. These are typically only used in hospitals and cleanroom manufacturing, though they can be used in a residential environment with serious allergy sufferers.
No matter what filters you choose, be sure to clean or replace them frequently (every three months or so) to make sure they’re not clogged and working as they should.
To get more info about air quality from our Sears Home Services experts, you can schedule a free in-home consultation.