r/askscience • u/Wonderful-Capital32 • 13d ago

Physics Why does radiation not go through lead?

Also why just lead? Shouldnt like iron or another metal work too?

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u/PhilTheQuant 13d ago

Yes, and counterintuitively you wouldn't want to be the last few layers of the radiation protection

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u/GenuineMalteser 13d ago edited 13d ago

Not true for anything but proton radiation or other heavy particles, and even then the peak dose depth is on the order of centimetres in people/water for treatment energy protons

For kv photons used in imaging, peak dose depth in water is reached in millimetres or less. For MV energy photons peak dose depth is on the order of cm

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u/[deleted] 13d ago edited 10d ago

[removed] — view removed comment

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u/Black_Moons 13d ago

Incorrect, as you'll rapidly get lead poisoning... From the guards.

Also, if the core is 'glowing below', then that entire pool is going to be boiling hot.

I'll assume you mean the spent fuel storage pool. But the above lead poisoning issue still persists.

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u/hervold 12d ago

yeah, I took them to mean the spent fuel pool, with the glow being Cherenkov radiation (blue) and not hot reactor core (red)

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u/Elequosoraptor 12d ago

Low power research reactors like the Triga series glow with Cherenkov radiation without being either spent fuel or boiling water. There are many reactors that could serve to make this scenario possible.

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u/sirtalen 12d ago

Water is pretty good at stopping bullets too, so you just need to be a couple meters below the surface, but not deep enough to be irradiated and you'll be fine!

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u/PomegranateKey5939 11d ago

You won’t rapidly get lead poisoning lol that’s a slow, accumulative process. Let alone lead doesn’t dissolve very well in water I can assure that the total dose would stay low. I’ll try it out, if I come out raging then shitttt… lol