Lots of good replies you got here in this thread. One thing that stood out for me in your original/opening post was the term "administration building". If this co-worker of yours is part of management, and you are not, then there's just no way on earth that I would ever say anything to him about your gear use if i were you. NO WAY! I was fortunate enough to learn my lesson the easy way when I was a moderator for the "GOT Fina" board back in 2003 and one of my fellow moderators turned out to be a NARC detective who infiltrated our BBing board so efficiiently that he became a moderator!!!
He went as far as to be the number one most influencial person in getting me nominated to become one of the board moderators, and once I was made one of the mods of that board he began sening me PM's and gave me his cell number telling me to give him a call. Once I did that, he got me on the phone and began asking me if I sell any gear, and when I told him "no I don't" he began grilling me about any fellow board members that I know who DO sell gear. I didn't tell him anything, and I never called him again. A month later a guy on our board got arrested for selling gear because of this same guy who I had called. Ofcourse by then the word was out and he was never on that board again, (as far as I know anyway).
Moral of the story....some guys will do anything to turn you in if they believe it will boost their career, be they an undercover detective, somebody in your work place management team, or even just a co-worker. Don't do it!!!! If he asked me something like that, I would just say: "do I use gear??? really??? C'mon now...even if I did, there would be no way I would talk about it anyway...get outta here dude!" The only way that I would even be seriously tempted to tell any of my co-workers is if they were pretty close friends to me OUTSIDE of the work place and in that case, if they were also into BBing, then I would tell them OUTSIDE of the work place, MAYBE. By the same token I would never discuss this with anyone I met at the gym, unless I knew them well outside of the gym, and for a long time.