Time to Clear the Air
February 11, 2014
The simplest thing you can do to improve your indoor air quality, after simply opening a few windows, is to use high-quality air filters and change them often. Since not many of us want to open our windows when the weather is extreme, air filters are your best bet.
Indoor air pollution is nothing to sneeze at; the Environmental Protection Agency puts it as one of the top environmental health risks. Helpfully, it recommends high-quality air filters as a way to counteract all the respirable particles in your home’s air.
Respirable particles are less than 2.5 micrometers in diameter and can lodge in your lungs when you inhale. And they’re things you don’t want in your lungs: viruses, bacteria, mold, and pollen spores, among others.
So, you’re standing in the air filter aisle; the selection is dizzying. How do you know which air filter is best? A few guidelines:
- Look for the filter’s MERV rating. This tells you the Minimum Efficiency Reporting Value…which means, it tells you the percentage of particles the filter traps. The rating is on a scale from 1 to 20. The higher the number, the better. You want at least an 8, but if you want 95% of those lovely respirable particles trapped, reach for the 11 or 12—especially if you have pets or anyone in your home with breathing difficulties. Anything above a 12 is hospital quality.
- Like in many things, price can be an indicator of quality. The least expensive kind of filters, flat or panel, have a MERV rating of 1 to 4 and basically only trap dust, not many respirable particles.
- Electrostatic filters are statically charged to draw large particles, such as dust and dirt. Unfortunately, that static charge only attracts about 20% of particulates. A few are reusable after washing, if you choose this type of filter, look for one with a lifetime guarantee.
- If you’re looking to remove odors, use a charcoal or activated carbon filter. The primary function here is to tackle pet odor or cigarette smoke; to get decent particle removal, get a high-quality pleated one for a MERV rating of about 8.
- For most of us, pleated filters are just fine. The pleats increase the surface area and proportionally stop more particles. The MERV rating for pleated filters ranges from 5-13; aim for the higher numbers unless you have someone with respiratory issues.
- The very best filters, especially if there are any respiratory issues in your home, are high-efficiency pleated filters. These have a MERV of 14 to 16. They are quite often marketed with “HEPA” somewhere in the title, but they are truly only “HEPA-type” because High Efficiency Particulate Air filters with MERV values of 17-20 require such specific installation that they are rarely installed in homes.
- It’s important to buy and install high-quality air filters. It’s just as important to change them at least every three months. If you have pets, smoke indoors, or have anyone in your home with breathing difficulties, it’s a better idea to change the filters every month or two.
The easy way to remember to change your air filters regularly? Buy several filters at once so you have them on hand, and write the date on the calendar when you should change them. Write the date installed on the end of the filter when you install it; then you’ll know how old the filter is at a glance.
Changing air filters takes about five minutes of your time. For such a small thing, they can greatly improve the quality of the air your family breathes.
Last Updated: June 09, 2023