High efficiency particulate air (HEPA) filters are generally considered to be the best way to eliminate many different forms of airborne contaminants from your indoor air. The HEPA filters typically found in home air purification systems are judged to be effective at removing 99.97% of particles sized 0.3 microns or larger. With this kind of efficiency and effectiveness, it’s hard to see why you wouldn’t want to include a HEPA filter as part of your home air purification system. While there are some other options including electronic air ionizers,HEPA filters are safe, effective and cheap to maintain. As long as you replace them regularly and keep up with a regular maintenance schedule for your entire home heating and cooling system, you should be able to enjoy clean, contaminant–free indoor air for many years to come.