Excitement

it's what you don't want in the toxic gas room.

At my institute, all gas bottles with toxic or explosive stuff in them are stored in the toxic gas room, which is very well ventilated, i.e. it has only three walls. Today I wanted to use some hydrogen in an experiment, so I went to egage the safety system and open all the valves (approximately 500 or so). But when I opened the main safety valve, I heard something you don't want to hear, especially after opening the 400 bar Hydrogen bottle: "Pshhhh!"

Further examination yielded more detail I would have been happy to remain ignorant of: The apparent leak, strong enough to move one of the many safety labels, was at the valve of the acetylene bottle, which is right next to the silane bottle. The gas system connects them all together, but normally they are, when not in use, seperated by big, fat valves. Valves, I might add, that are not supposed to hiss. Now acetylene is highly combustible of course, hydrogen explodes quite nicely, but the real bummer is silane, which is pyrophoric - in air it spontaneously combusts.Wich is normally just annoying - with a bit of hydrogen and acetylene however, it could get interesting. For a moment my eyes went even bigger, to properly process what might the last image they and everybody in the building would ever see, and then I slammed the nice, red emergency-stop button. In fact, I may have slammed it a couple of times, with vigour.

Then I went into the next room, shut off the klaxon, and called my professor. "Christoph," I said, "there may be a small problem with the toxic gases." Despite the utter calmness of my statement, he must have suspected something, because he came remarkably quickly.

In the end, all the excitement was over hot air, or pressurised air, as it were. All the big valves are  controlled by pressurised air, and one of them had stuck half open because of the cold - during the night we had around minus ten celsius, and as mentioned above, the room is lacking a wall. For safety reasons.