MERV 8 filters are commonly used in residential buildings to capture air contaminants of 3.0 microns or more, trapping medium-sized particles such as aerosols, mold and dust. While these filters can be effective at blocking larger particles, they are not suitable for people with allergies, asthma, or other health or respiratory problems. Studies have found that filtering recirculated air can provide a variety of benefits, but it is important to choose the right filter for your home. As an HVAC professional with more than 40 years of experience, I have seen dozens of systems destroyed using highly restrictive filters with a high level of MERV.
Choosing the perfect air filter is incredibly important because choosing one that is too high or too low can be hazardous to your health and your home. MERV 1-4 filters are virtually ineffective because they only trap the largest particles and are considered the minimum threshold for air filtration. For most homes, a MERV 8 filter is an appropriate way to keep the air healthy. However, it's important to consider your specific needs when choosing an air filter for your home.
If you have allergies or respiratory problems you may need a higher rated filter such as a MERV 13 filter. It's also important to make sure you choose an air filter that is compatible with your boiler or air conditioner. Using an air filter with a MERV rating higher than that recommended by the boiler or air conditioner manufacturer may affect its performance. Fortunately, I have a 3D printer and I have printed a mask with a MERV 13 filter. To achieve the MERV-13*, a filter has to trap 90% of the particles in the range of 3 to 10 μm, 85% of the particles in the range of 1 to 3 μm (where the PM2.5 are) and 50% of the particles in the range of 0.3 to 1 μm (the very, very small things).
By the way, offices have a variety of Merv filters and air conditioning systems use Merv filters; in both cases, they do not use fiberglass. In conclusion, it is important to consider your specific needs when selecting an air filter for your home. A MERV 8 filter may be suitable for most homes but those with allergies or respiratory problems may need a higher rated filter such as a MERV 13 filter. It is also important to make sure you choose an air filter that is compatible with your boiler or air conditioner.