A typically British response..
We had nice sticky out kill switches and after being activated several times, ok I did it once simply by stacking boxes on a table handily put under a switch, management came up with a missive to prevent accidental activation.
This turned out to be a load of plastic cups and me trotting around the place covering the red bit with a plastic cup. Seemed to work as I can't recall them being set off again.
Oh yes and we had the halon gas stuff and raised floors. One data centre had an electrical fire that caused the halon to release.
The whole computer room was wrecked as the injectors were under the raised floor and several floor tiles went into action and became part of the PDP11's.
On the plus side room was refurbished and had the injectors sticking out of the cieling tiles.