When it comes to air filtration, the Minimum Efficiency Report Value (MERV) rating is an important factor to consider. MERV ratings measure how effectively a filter prevents dust and other contaminants from passing through the filter into the air stream. Oven filters with MERV ratings between 6 and 8 are the most economical and are considered to be the minimum of efficiency. A MERV 6 filter is the entry level option and is primarily focused on providing a sanitary air environment rather than cleaning it of most contaminants and allergens.
It will trap basic household dust and pollen, but is not considered to be the most effective at trapping large portions of particulate matter in the air. Filters in the MERV 5-8 range can also trap particles with a size of 3.0-10.0 microns, but are more efficient in doing so. A MERV 5 filter will trap up to 34%, the MERV 6 will stop 35-49%, the MERV 7 will prevent up to 69%, and the MERV 8 will trap up to 85% of the particles. ASHRAE recommends MERV 6 or higher, while the U. S.
Department of Energy recommends MERV 13 and LEED recommends MERV 8 as a minimum. If you're on a tight budget, such as a college kid's budget, then a MERV 6 filter is your best option. It's not the best thing for indoor air quality, but it will keep dust out of the air system. However, if you're looking for more protection against fine particles, then you should consider filters with a MERV value 13-16. These are the most restrictive and can trap the smallest particles, such as bacteria, tobacco smoke and burnt wood. A higher MERV rating may mean slightly more restricted airflow; however, most current HVAC systems are capable of handling a MERV 11 air filter without additional system stress. In standard cases, a MERV 8 air filter is considered a more than adequate option, but it may not be enough when it comes to combating increased outdoor air pollution, pet fur and dander, or asthma and allergy triggers.
Using an air filter with a MERV rating higher than recommended by the manufacturer of your oven or air conditioner may impair its performance. A MERV 6 filter will remove most allergens from the air; however, it is not recommended for people with severe allergies or asthmatics. Leaving a dirty air filter in place or using a filter that is too restrictive can cause low airflow and possibly cause a system malfunction. As long as they are replaced on time, MERV 6 filters are the best option for those who want quality air filtration without breaking the bank. If you use a higher MERV rating that traps more particles, you may need to change the filter more often.