If you're looking for a filter to trap pollen, dust mites, and hair, a Merv 8 filter is the ideal choice. It's much better than fiberglass filters and is still quite reasonably priced. This type of filter will be able to trap anything larger than 3 micrometers, which is enough to capture common pollen, dust, and debris. On the other hand, if you have allergies, pets, or live near smoke pollution, a Merv 13 filter is the best option.
It specializes in trapping tiny particles such as bacteria in the air and smoke. In addition to everything the Merv 8 and MERV 11 filters trap, the MERV 13 filters also trap tobacco smoke, fire smoke, contaminants in body fluids released by sneezing and coughing, and bacteria. The difference between MERV 8 and MERV 13 rated filters is reduced to two microns. The American Society of Heating, Refrigeration and Air Conditioning Engineers created the MERV filter rating system as a domestic and global industry standard rating system.
The ratings range from 1 to 20, with 1 being the lowest filtering capacity and 20 being the highest filtering capacity. Filters rated 5 to 8 can capture contaminants such as hairspray, cleaning and dusting aids, cement dust, and mold spores. Filters rated 1 to 4 can capture larger particles such as carpets and textile fibers, dirt particles, spray paint and sanding dust particles, dust mites and pollen. The highest merv rating that is safe for residential use is MERV 13, although such a high rating is rarely needed in a residential home unless someone has severe dust allergies or asthma and needs advanced air filtering. Even though pleated filters have a slightly larger initial pressure drop, it's not significant enough to cause any damage to your HVAC system as long as you change filters regularly.
Strict building codes and an increase in foot traffic generally mean that commercial properties must opt for a filter with a higher MERV rating. So the question arises: Is it really worth upgrading from MERV 8 to MERV 13? Is there a big difference between the two? The answer is yes; the main difference between the MERV 8 filter and the MERV 13 filter is that the latter includes stronger protection against airborne bacteria and viruses that spread through airborne droplets. It's not just about the amount of “matter” the filter traps; it's also about the size of the particles they capture. The air cleaner is literally a barrier between the HVAC system and the ventilation grilles, reducing the ability of air to pass through the vents into the actual system. The filters in this range will remove particulate matter and keep your home's airflow clean enough without overloading your HVAC system. In short, if you need a filter to trap pollen, dust mites, and hair, a Merv 8 filter should do the job. But if you have allergies, pets, or live near smoke pollution, choosing a Merv 13 filter is your best bet.