Вот например из интересной дискуссии в реддите (англ.):
Here's a funny anecdote about codewords; a friend of mine was working in a Belfast hotel in the early 90's. She worked at reception and received a phone call to say a bomb would go off in one hour. She freaked the fuck out. The manager calmed her down and asked her to repeat the conversation verbatim. Then the manager told her to go back to work as no codeword had been given and the threat was just a hoax. My friend chose to go about 3 miles in the opposite direction, but the manager was right - it was just a hoax. People can be very pragmatic about these things.