Ahh, the fun of Health and Safety.
We had a good one here a couple of years ago. Someone leaving a meeting room dropped a cup of water on the floor. It's carpet, so no slip risk, but H&S insisted on popping one of those yellow "slippery floor" sandwich boards right in the middle of the corridor, just to the right of the meeting room.
Half an hour later, another meeting ends, someone leaves the room and turns right whilst chatting to a colleague, doesn't notice the yellow board, trips over it and is sent flying.
When you are trying to alert people to a non-existant hazard by creating a much more blatant hazard, you have to ask if you've really thought things through...