Q. What is a MERV rating?
MERV stands for the Minimum Efficiency Reporting Value, and is a measure of a filter's worst-case efficiency performance. The higher the MERV rating, the more efficient the filter. MERV ratings range from 1 to 16.
The higher the rating the more particles the filter can remove. Higher rated filters allow less air to flow through though and can force your furnace to work harder and possibly malfunction. A MERV rating between eight and 11 is adequate for most homes. To be safe, you should check if your furnace manufacturer has a maximum MERV rating your model of furnace can use.
MERV 8 pleated filters are able to handle pollen, human hair, dust, debris and dander.
MERV 11 pleated filters are able to handle all-of-the-above plus mold spores, car fumes and smog.
MERV 13 pleated filters are able to handle all-of-the-above plus tobacco smoke, smoke, bacteria, virus carriers and microscopic allergens.
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• Fiberglass (MERV: 2-3) is a commonly used material, but these inexpensive filters allow more pollutants to pass into the system than other materials.
• Polyester/cotton pleated (MERV: 6) disposable air filters are an affordable option and provide average cleaning and removal of small particles, as long as they are replaced frequently.
• Electrostatic cotton and paper (MERV: 10) provides excellent filtering properties with regular replacement. They are more expensive, but are a good option for homes with pets or smokers.
• Permanent, washable filters (MERV: 8) are an affordable and environmentally friendly choice, but they may not be able to capture microscopic particles and must be cleaned frequently.
• High efficiency pleated (MERV: 13-16) air filters are the most expensive but they provide exceptional filtering capabilities and system protection. They are generally used most often in hospitals, but people with respiratory diseases may benefit from them in their homes.
Please Note: Due to the thickness and air pressure needs, they cannot be installed in all systems.