Sitting at a traffic light about a half hour ago and the guy in front of me was burning oil real bad and chugging smoke. Turned on Bio-Weapon Defense Mode and only got a brief whiff of the truck then it went away. What I'm impressed by is that it removes all smells so that you're left sniffing the air trying to smell something, lol! I also work right across the street from the Columbus Airport (CMH) and have waves of jet fuel fumes that come over if the wind is blowing the wrong direction or if you happen to be driving down the road at the end of the runway right after a plane has taken off. I've got headaches from this in the past because it was so overpowering, but not anymore!