The MERV rating of an air filter is a measure of its effectiveness in preventing dust, allergens, and other contaminants from passing through the filter and entering the air stream. MERV ratings range from 1 to 16, with higher ratings trapping small particles more effectively than lower ratings. Hospitals, nuclear power plants, and other demanding environments often require air filters with a MERV rating of 16 to 20. For residential, commercial, and general hospital use, filters with a MERV rating of 16 or lower are considered suitable. Using an air filter with a higher MERV rating than recommended by the boiler or air conditioner manufacturer can affect its performance.
The worst test score determines the MERV classification, as it is intended to measure the “minimum efficiency” of the filter. A MERV 8 filter should be sufficient for homes with few occupants and no pets, while homes with more people and some pets need a MERV 11 filter. The use of higher rated filters with higher mervs can have a positive impact on indoor air quality. These filters can help remove more contaminants from the air, resulting in a reduction in common allergic symptoms such as runny nose, persistent sneezing, sore throat, skin rashes, eye irritation, headaches and fatigue. However, it is important to note that using an air filter with a higher MERV rating than recommended by the boiler or air conditioner manufacturer can affect its performance. Therefore, it is important to consult with an expert before making any changes to your home's HVAC system.
