You wanna really freak yourself out, walk into a room after an SF6 (surfer hexaflupride) release. It’s another, less commonly used, smothering gas. Usually around really high voltage stuff. When I was a young fireman, we went on an alarm call in a manufacturing clean space. We met with staff who said they thought it was a misfire of the system because their instruments didn’t show any issues. They left out the SF6 detail so we just thought it was maybe a Halon system, at least I did. We walked in and looked around. Didn’t really see anything. My Captain called out to me from across the room and it sounded like his voice was about 6 octaves lower. I answer him back and sounded the same! We both freaked the hell out and ran out of the room trying to put our breathing apparatus on as we were running. The staff outside met us laughing. ‘Never been around Sulfer Hex before, huh??’ Scared the bejeejus out of me!! 

Think of it as the exact opposite of helium. Goes away just as fast!

Ryan/// ~sigh~ I blew up another bowl. Moke told me "I made the inside bigger than the outside".