There are a host of filtration and air purification products out there. We know that your family's health is important, but it can be hard to make sense of it all. Below is a brief overview of the types of products available, as well as the advantages and disadvantages of each.
Media Filters
The most basic type of air purification is filtration. And the most basic filtration products out there are media filters. These are typically installed in a cabinet on one side of your furnace and look like folded paper or fabric inside a cardboard frame. As your furnace pulls air into the system, particulates are trapped in the filter. These filters range in both size and efficiency, from standard 1-inch filters, to super-efficient 5-inch filters. It's not all about thickness, although the best media filters are 5-inches thick. Only one size will fit in your system, so choose your furnace filter wisely when you are having your furnace installed. The efficiency rating is expressed in a MERV value, which ranges from MERV 6 (very basic) to MERV 16 (hospital-grade). All media filters must be replaced periodically; however,
the better filters need to be replaced less often.
Electronic Air Cleaners
Electronic air cleaners are installed in place of a media filter, next to your furnace. Instead of trapping particulates in folded media, however, electronic air cleaners have an electric charge. As particulates pass through the pre-filter, they get the opposite charge, and ZAP! they are attracted to the charged "fins" of the electronic air cleaner. These are more efficient than all but the best media filters. Best of all, they don't need to be replaced! Just wash out the cells every 6 months, and you're good to go!
UV, PHI, and PCO Lights
There are different competing technologies out there, but all these products are lights that shine on air passing by and kill bacteria, viruses, mold and mildew. These are excellent choices if you require the purest air in your home. The bulbs generally need to be replaced every 3 years or so.
Multi-Stage Air Cleaners
These can get really complicated and confusing, but they are also installed next to your furnace, in place of a media filter. They usually involve some sort of light, kills any viruses and bacteria in the air passing through it, as well as a super-efficient media filter, and an odor filter. The cells are all connected in one replacement unit, and these typically need to be replaced every 6-12 months.