The other people in the room got a couple years’ worth of rads from his mistake didn’t they?

I’m sure they rationalized not using an apparatus for this due to embrittlement, thermal expansion, response time, or all three. But from the perspective of someone looking back on this era 50 years later (now 80), Jesus fucking Christ.

Carpenter’s pencils as spacers would have saved his life.

In fact Wikipedia says he was a dumbass:

> The standard protocol was to use shims between the halves, as allowing them to close completely could result in the instantaneous formation of a critical mass and a lethal power excursion.

> By Slotin's own unapproved protocol, the shims were not used. The top half of the reflector was resting directly on the bottom half at one point, while 180 degrees from this point a gap was maintained by the blade of a flat-tipped screwdriver in Slotin's hand. The size of the gap between the reflectors was changed by twisting the screwdriver. Slotin, who was given to bravado,[11] became the local expert, performing the test on almost a dozen occasions,