MERV 9-12 Rating Filters in this range can trap more than 85% of particles of size 3.0-10.0 microns. A MERV 9 will trap less than 50% of the 1.0-3.0 micron size particles, the MERV 10 will stop at 64%, the MERV 11 will get up to 79%, and the MERV 12 is capable of trapping up to 89%. The MERV 12 air filter traps about 89% of particles from 1 to 3 microns and more than 90% of sizes from 3 to 10 microns. The MERV 13 air filters even provide additional filtration power against fine particles compared to the MERV 11 filters.
The additional benefits of MERV 13 air filters are that they can filter smoke, airborne viruses and smog. They are particularly useful in heavily polluted areas, areas that are often affected by wildfires, or to help prevent the spread of disease. As with any increase in the MERV level, there is an associated price difference and airflow resistance. In 1987, the American Society of Heating, Refrigeration and Air Conditioning Engineers designed the MERV rating scale to provide a more accurate picture of an air filter's capabilities.
The higher MERV rating means that an air filter will capture the most dust, while the lower rating means that a filter will capture the least amount of dust. For example, if you have someone in your household who suffers from allergies, you may want a higher MERV rating. It's best to comply with oven manufacturer's recommendations or consult an HVAC professional to determine exactly which MERV rating is best for your specific system. If you're really not sure which MERV rating to use, you can have professionals make a recommendation for you during a routine HVAC basic maintenance visit.
If you're wondering what MERV rating your unit can handle, there are often a few simple steps you need to follow. In these cases, a MERV 11 air filter can provide additional benefits and capture a wider range of particles that would pass through a MERV 8 filter. While these issues can be fixed, you don't need to purchase the air filter with the highest MERV rating. MERV 17 to MERV 20 filters are commonly used in operating rooms, cleanrooms, and other settings that require absolute cleanliness.
Filters with higher Merv ratings should be changed more frequently (at least every three months) to avoid restricted airflow that can cause the system to operate inefficiently or even damage it. A higher MERV rating often means lower airflow, which can make the system work harder and use more energy to do its job. If your HVAC has a permanent split condenser fan, a higher MERV rated air filter will interfere with it and cause lower airflow. While you may automatically think that a higher MERV rating means a better air filter, that's not always the case.
In general, filters with a MERV 16 rating or lower are considered HVAC system grade filters for residential, commercial, and general hospital use. Filter technology has grown by leaps and bounds over the years, and MERV ratings are designed to help us determine the most effective and efficient air filter options for heating and cooling systems and more. Using an air filter with a MERV rating higher than recommended by the manufacturer of your oven or air conditioner may impair its performance.
