I guess not an analysis since that was done by overthinkingit.com. I just want to make sure some of my math holds up. I'll break that out of the synopsis for ease of viewing.
A 20kT nuclear bomb (Based on the 1957 Operation Plumbomb testing) would emit 10 rem of high energy gamma radiation at 300m. 1 cm of lead would provide a 50% drop. The calculation of rem is based on Rive's comment even though it's nuch larger. I admit I can't find a reliable gamma radiation exposure calculator like Hologram0110 suggested.
A body flying at 38.32 m/s feels a force of 46.2 G.
Hitting the ground at that speed would be like hitting a brick wall going 60 mph (thanks QuantumPion)
The college history class is a joke, but the record is 14 minutes.
I did hit a snag. According to Wikipedia, a kT explosion would result in Thermal radiation effective ground range of 2000 m. Meaning Jones would literally be standing in the middle of a firestorm. He would have to be at least 4000 m away just to get away with third-degree burns. So, we can assume he was immediately burned to a crisp when he got out of the fridge?
http://en.wikipedia.org/wiki/Effects_of_nuclear_explosions