Air filter performance is measured by the filter’s ability to trap particles of a certain size. The smaller the particles the filter traps, the more efficient it is. The process of rating air filters involves the standardized MERV scale (Minimum Efficiency Reporting Value). This scale ranges from 1 to 16 with HEPA (High Efficiency Particulate Air) filters ranging from 17 to 20.
MERV Ratings and What They Mean
Here’s a look at what each MERV rating means in terms of particles the air filters can trap.
- MERV 1-4: Washable or throwaway flat or panel air filters in this range come standard in HVAC equipment. They trap things such as textile and carpet fibers, dust mites, pollen, spray paint and other particles larger than 10.0 microns.
- MERV 5-8: Pleated, cartridge and throwaway synthetic panel air filters fall in this range. They provide better residential air quality control by trapping dusting aids, hair spray, mold spores and other particles between 3.0 and 10.0 microns.
- MERV 9-12: Rigid box air filters several inches deep provide superior residential air quality control. Filters with these ratings can trap welding fumes, auto emissions, milled flour, humidifier dust, some types of bacteria and other particles 1.0 to 3.0 microns.
- MERV 13-16: These closely resemble air filters rated between MERV 9 and 12, but they can trap even smaller particles. Used in smoking lounges and hospitals, these filters can trap tobacco smoke, all types of bacteria and other particles between 0.3 and 1.0 microns.
- MERV 17-20: HEPA filters fall in this category. They are used in clean rooms and around radioactive and carcinogenic materials. These air filters can trap carbon dust, combustion smoke, viruses and 99.999 percent of all particles smaller than 0.3 microns.
As a Calgary homeowner, you’ll want to choose air filters within the MERV 5 to 12 range. Any higher than this and the pressure becomes too high to maintain proper airflow. Make your selection based on your budget and indoor air quality needs.
For more information regarding air filters for better indoor air quality, please contact Arpi’s Industries in Calgary. Our experience serving homes and businesses in Alberta dates back more than 55 years.
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