|
|
One kind of filter that many air cleaners use is called an electrostatic precipitator. This is basically just a form of an ionizer. It forces the air past a metal plate in an area where the air is charged with electricity, forcing dirt and other particles to stick to the plate. These kinds of filters are cheap and generally don't need to be replaced - you just need to wash the plate when it gets covered in dust.
One downside is that some versions of this can generate ozone, a potentially harmful gas. There's a lot of dispute about whether it's actually dangerous at the low levels these create, but it's something I'd recommend avoiding just in case.
Sources and Useful Links:
http://en.wikipedia.org/wiki/Electrostatic_precipitator
Return to Air Cleaners / Air Purifiers Guide Home Page