Tickling the Dragon: Nuclear accidents in the US and Russia - Boing Boing:
My father was in the room with Slotin, and if Slotin hadn't done what he did I would not exist.
He described a brief blue glow in the room when Slotin lifted the plutonium sphere, and quickly leaving the room. He was about 20 feet away from the plutonium at the time, and Slotin was standing between the sphere of plutonium and the group watching him. My father's radiation badge (a square of photographic film sealed inside an envelope) showed a significant exposure that day, but fortunately not a dangerous one.
Some have questioned whether a Cerenkov radiation flash (the blue glow) could have ocurred under the conditions there that day, but my father believed it was due to the neutron radiation interacting with the water in his eyeballs.