When you switch from a cheap fiberglass air filter to a MERV 8 filter, you add a lot more protection. This rating is sufficient for air filtration in average residential homes, trapping mold spores, pollen, and most cleaning products. However, individual circumstances may require a filter with a higher MERV rating. There are four levels of filters that you should be aware of.
The entry level is a MERV 6 filter, which is economical and will trap basic household dust and pollen. MERV 1 to 4 are effective in controlling larger particles, such as sanding dust, spray paint dust, lint and carpet fibers. MERV 9 to 12 are effective for controlling humidifier dust, lead dust, vehicle emissions and welding fumes. When choosing between a MERV 8 air filter and a Merv 11 air filter, it's important to note that a high merv rating generally means that the filter is thicker and your HVAC system will have to work harder to circulate air throughout the house.
While Merv ratings reflect a filter's ability to trap microscopic and macroscopic particles, MPR ratings only rate a filter based on its ability to remove 0.3 to 1 micron particles. If you're worried about the effects of inhaling fine air particles, that's another reason to choose a Merv 11 air filter instead of a MERV 8 air filter. Filter technology has grown by leaps and bounds over the years, and MERV ratings are designed to help us determine the most effective and efficient air filter options for heating and cooling systems and more. If your home's HVAC system is not capable of handling MERV 13, opt for a filter with the next highest possible rating.
Another factor driving the popularity of MERV 8 filters is that they are inexpensive and easy to maintain. MERV 13 filters remove bacteria, tobacco smoke, car fumes, insecticide dust, pet dander, and more. A higher MERV rating means that a filter is more effective at trapping microscopic pathogens and particles that we would prefer not to inhale. Choosing the right MERV rating is an important decision in terms of total cost, air quality, and product durability.
To determine the MERV, the performance of an air filter is determined by measuring the particle counts upstream and downstream of the filter being tested.