The Next Time You Go Shopping For An Air Filter, Look Up MERV

If you're concerned about your indoor air quality, check the MERV rating on your air filters next time you buy them. Many manufacturers previously advertised that their particular filter would trap certain pollutants. Some were honest, and some may have been stretching the truth. The government has devised a standard testing system for forced-air filters so that there's consistency in the manufacturers' claims.

MERV stands for "minimum efficiency reporting value." As these filters are tested, they are assigned a MERV rating. The higher the rating, the better the filter removes particles from indoor air. Low ratings catch things such as dust particles and other larger contaminants in your indoor air. Higher ratings catch both the larger and smaller, unseen particles.

Here's a breakdown of MERV ratings and what they mean:

• Filters rated 1 to 4 on the MERV scale catch paint dust, carpet and fabric fibers, household dust and dust mites.
• Those rated 5 to 8 will filter out pudding-mix particles, hair spray and mold spores in addition to larger particles.
• 9- to 12-rated air filters catch all the above plus auto emissions, flour dust and some viruses.
• Filters rated 13 to 16 catch tobacco smoke, all bacteria and droplets from coughing or sneezing.

As you can see, the higher-rated MERV air filters are the most effective at trapping the most types of particles. But those highest-rated filters could slow the airflow through your HVAC system if it's not equipped to work with them, leading to equipment damage or ineffective or inefficient operation. It is smart to consult a heating and air professional before buying the higher-rated filters.

For more information on air filters and MERV ratings, contact our indoor air experts at Santa Fe Air Conditioning & Heating. We can give you the information you need to make a wise choice. In fact, call us with any of your heating and cooling questions. We're always ready to help.