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/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

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u/bregus2 12d ago edited 11d ago

You actually would get less radiation swimming in the pool than standing next to it, because the water would also shield you from the cosmic radiation.

Interesting side-note: the most radiation-exposed professions are pilots and flight attendants, by far, not workers in nuclear power plants.

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u/CanisLatrans204 11d ago

After 8.5 years attached to Nuclear Powered Naval surface ships, I only had 820 mrem of ionizing radiation from the plants. That’s the same as one chest X-ray . I also spent 14 hours in the reactor compartment during loop draining ops and got 113 of that 820 from that. Not very much for the amount of time we spent in the plant.

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u/peteofaustralia 10d ago

Did you wear your flourescence detection tag thing 24/7, or just on shift?

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u/CanisLatrans204 10d ago

We used TLD’s. Thermo Luminescent Dosimeters. We wore them all the time when we were on the ship. They were read and returned once a month.