A filter's MERV rating measures how efficiently it removes contaminants from the air stream based on the size of the particles it can effectively capture. MERV 5 fiberglass non-pleated air filters provide up to 20% efficiency for filtering particles between 3 and 10 microns in size (such as mold spores, dust aids, and cement dust). Non-pleated panel air filters are installed in HVAC systems to capture contaminants in the air stream. This improves indoor air quality and prevents contaminants from accumulating on the equipment and damaging it.
Non-pleated panel polyester air filters or fiberglass air filters are commonly used in furnaces and central air systems in residential and commercial buildings. These flat air filters are commonly used to capture large particles between 3 and 10 microns in size (such as mold spores and cement dust).