ULPA filters are the highest quality air filters available, with a MERV rating of 20. This rating indicates the filter's ability to capture particles in the air, such as tobacco smoke, oil smoke, insecticide dust, charcoal dust, and even some viruses. HEPA filters must meet the standards for a MERV of 17 or higher to provide true HEPA filtration. The acronym MERV stands for Minimum Efficiency Report Value and is used to indicate the effectiveness of the filter.
Homeowners often want the filter that traps the smallest particles, such as HEPA filters with the highest MERV ratings. The MERV rating of an air filter is based on the size of the particles in the air that it will capture as air passes through it. Filters in residential, commercial, and hospital HVAC systems generally have a MERV rating of 16 or lower. Filters with a MERV rating of 9-12 trap at least 85% of air particles 3 to 10 microns in size, 50 to 90% of 1 to 3 microns, and more than 20% of air particles smaller than 1 micron.
Complex HEPA filters exceed the typical MERV rating scale, making them the most efficient and popular choice for many industries. They are mostly constructed with a flat surface area, but since fiberglass is thinner and tighter throughout the filter frame, they are more effective than MERV 1-4 filters. If you're looking for an air filter that offers superior filtration, ULPA filters are your best option. To ensure you get the best performance from your filter, it's important to ask a qualified HVAC technician to inspect your equipment and recommend the right MERV filter for you.