What is the banana equivalent dose of working 8 hours a day in an old office building with granite stone floors, and granite wall paneling? I've read that all granite is slightly radioactive.
Roughly 0.18 to 3 mSv per annum [0]. (EU regulations limit it to 3 mSv/a maximum [0]).
One banana is 0.1 µSv [1].
The granite is therefore 0.18 mSv / 0.1 µSv = 1800 bananas.
This is compared to 4 mSv normal yearly background dose [1]. The granite increases background radiation by 0.18 / 4 * 100 = 4.5%. The yearly dose from natural potassium in the body is 0.39 mSv, so I wouldn't worry about the extra 0.18 mSv if I were you.
You're at much greater risk if you live in a house which used reinforced concrete with steel from the Ciudad Juárez accident - after that accident, 109 houses were demolished. [2] [3]
One banana is 0.1 µSv [1].
The granite is therefore 0.18 mSv / 0.1 µSv = 1800 bananas.
This is compared to 4 mSv normal yearly background dose [1]. The granite increases background radiation by 0.18 / 4 * 100 = 4.5%. The yearly dose from natural potassium in the body is 0.39 mSv, so I wouldn't worry about the extra 0.18 mSv if I were you.
You're at much greater risk if you live in a house which used reinforced concrete with steel from the Ciudad Juárez accident - after that accident, 109 houses were demolished. [2] [3]
[0] https://www.nature.com/articles/jes200944
[1] https://xkcd.com/radiation/
[2] https://en.wikipedia.org/wiki/List_of_civilian_radiation_acc...
[3] https://news.ycombinator.com/item?id=24891947