Furnace Filter Merv Rating

In general filters with a rating of merv 16 or below are considered to be hvac system grade filters for residential commercial and general hospital use.

Furnace filter merv rating.

At the very lowest merv rating 1 4 your filter will still capture pollen dust mites cockroach debris sanding dust spray paint dust textile fibers and carpet fibers. Below is a table grouping merv ratings by particle size. Merv filter ratings and efficiency. You might have been using furnace filters with one that is too low or too high for your furnace without knowing it.

Merv ratings indicate how effective a filter is at keeping different particles out. Filters within a merv rating of 17 20 are almost never necessary in a residential home. Ranging from 1 to 20 the larger the number the better the filter is at catching small particles. If the rating is too low potentially dangerous or damage causing particles can easily slip by.

The rating indicates the size of particles the air filter is designed to capture. Merv ratings range from 1 to 16. Particles are measured in microns and range from carpet and textile fibers greater than 10 microns to microscopic bacteria less than 0 3 microns. The higher the merv rating on a filter the fewer dust particles and contaminants can pass through it.

Merv 17 through merv 20 filters are typically used in surgical operating rooms clean rooms and other contexts that require absolute cleanliness. Merv stands for minimum efficiency reporting value which is a rating system designed by the american society of heating refrigerating and air conditioning engineers.