Funny story, I was in the US Air Force and worked on munitions. Was on temporary duty at another base and had to process thousands of rounds of spent 20mm shells. It was always a dirty job because of the spent propellent. The next day I had to fly back to my home base. This was a couple of months after 9/11. As I was going through TSA they swabbed my bag and shoes for explosives. Needless to say every damn alarm went off. Once I showed them that I was traveling on official military ordered they let me go, but I'd be lying if I didn't admit I was sweating pretty bad.