OK, this is an interesting discussion. Does it actually "detect" particulates?

My personal experience is that it does NOT eliminate all odors. In fact if I'm right behind an older bus, I can definitely smell the diesel exhaust. And when I'm on the NJ Turnpike between say Interchange 13 and Interchange 16, the "Turnpike" smell is quite strong and breaks through the "A" function. Those of you from NJ know what I mean when I say "Turnpike smell" . So there are certain situations when the "A" function appears insufficient, and I'm forced to go to "Full-time recirculate". Would be interesting to see if others have seen the same....