Low-background radiation steel is any steel produced before the Trinity Test. Unlike modern post-nuclear steel, low-background steel does not contain radioactive impurities, making them ideal for use in devices that require high sensitivity to radiation. Most of the steel are sourced from pre-1945 shipwrecks.
A body counting room (for measuring radiation within the human body) made entirely from pre-World War II steel.
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1945 atom bomb containment vessel - photos
Nuclear waste cask being transported - GIF
Map of every nuclear explosion since 1945 - photo
Gilbert U-238 Atomic Energy Lab toy lab set - photo
Manhattan Project scientist's A-bomb pin - photo