Jeeze, this guy must have some serious issues. I don't know, maybe its has something to do with how he was raised, but theres really no excuse for how he behaved. Shit like that doesn't need to happen. Good for you for not kicking his retarded ass, though. That would have just made things worse.

However, making joke just within earshot would have been totally acceptable. Something like "Hey S, can you turn that fan on? It's a little 'dusty' in here. Lets blow some of that shit outside." or "Hey Kim, you know, that reminds me, we haven't dusted in a while. Maybe we can get that guy to help?"