Re: Anyone for a swim?
I met someone who had once fallen into a swimming-pool reactor -- the rail around the top gave way when he was leaning over the edge to hook a sample of [information deleted, Official Secrets Act 1911 as amended] onto a pulley line to be lowered down to near the core for irradiation purposes. He didn't go in all the way, just his leg and foot as he grabbed for the rail supports but Health Physics had a field day with him nevertheless.
Cherenkov radiation is like nothing else on Earth when you see it with your own eyes, by the way.