Concrete is radioactive, I'm reminded of this fact when I go into a concrete parkhouse and feel the heat, and I don't particularly care if its hot due to radiation or hot due to heat energy from cars being stored - either way, the darn places are uncomfortable and I avoid them.

I'm not particularly bothered if I'm "wrong", its just a cute thing to say .. "oh, its so radioactive in here, lets get out.."

It sounds more crazy than cute to me.

Well, next time you walk into a stinking hot concrete bunker, say to yourself "I wonder if I know what the word radiation means, hmmm.."