I was just looking at the new BestAir 1300 series filters (product number "PF<height>x<width>"), combining a MERV 11 filter with odor control in a low cost filter. They claim to use "carbon fusion", with new patents pending, and the filters don't look like the typical carbon-impregnated fibers; the filter is gray. So, I'm wondering how that compares to all the varieties of carbon filters on the market.

There's granular activated charcoal (GAC), which can be fairly expensive and loses activity quickly if not protected by a MERV 11 filter. Then there's "dry processed carbon composite media" (Flanders' DPCC), "Celbond Particulate Structures Technolgy" (Koch's Odorkleen), whatever those mean, and the typical carbon-impregnated fibers. Some are optimized for acid gases, others for alkaline ones. The carbon-impregnated type filters seem to vary widely in quality and ozone removal effectiveness.

Obviously the more carbon weight there is, the more absorption can happen, but I'm wondering also about things like catalytic ozone removal. I wonder if this "carbon fusion" filter corresponds to the mysterious filter mentioned in "A pilot study of energy efficient air cleaning for ozone" (2002), Lara A. Gundel, Douglas P. Sullivan, Gregory Y. Katsapov and William J. Fisk. It is described as a "filter that contained a thin layer of small activated carbon particles in a pleated configuration." It seemed rather effective for ozone removal.

I wish there was some standard way of comparing all these carbon filters? Which is most effective for ozone, odor absorption, etc, etc? Who has the time to try them all and evaluate them?