MERV filters 9 to 12 are good filters for general household use. They remove most of the dust we see in homes and offices. They generally allow enough air to flow through the oven filter to allow the blower to stay cool. Its cost is usually moderate and is within many budgets.
The American Lung Association recommends a filter with a MERV rating of 13 or higher (as long as it works with your central air system). The worst filter performance in all three particle sizes during each of the 6 cycles is used to determine the MERV rating of the filters. Using an air filter with a MERV rating higher than recommended by the manufacturer of your oven or air conditioner may impair its performance. 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 trap small particles more effectively than filters with lower MERV ratings. The Minimum Efficiency Report Value (MERV) rating for an air filter measures how effectively the filter prevents dust and other contaminants from passing through the filter into the air stream. In general, filters with a MERV 16 rating or lower are considered HVAC system grade filters for residential, commercial, and general hospital use.