Comparing RBE to relative penetrating power?

AI Thread Summary
Relative Biological Effectiveness (RBE) measures the biological damage caused by different types of radiation, with alpha particles having the highest RBE despite their low penetrating power. This discrepancy arises because RBE does not consider the source of radiation, particularly whether it is external or internal. Alpha radiation, while highly damaging at close range, cannot penetrate the skin, limiting its overall harm to humans compared to other radiation types. The discussion highlights that RBE is a measure of damage per kilogram of tissue, not a direct indicator of overall harm. Understanding these distinctions is crucial for evaluating radiation risks.
Eve Litman
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Relative biological effectiveness is a factor that radiation dose is multiplied by to account for differences in biological damage by varying types of radiation. RBE is higher for alpha particles than any other, yet the relative penetrating power of alpha radiation is the smallest of the four types of radiation, and alpha radiation is not the most harmful to humans. Why doesn't RBE correspond to how harmful a type of radiation is?
 
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Eve Litman said:
Relative biological effectiveness is a factor that radiation dose is multiplied by to account for differences in biological damage by varying types of radiation. RBE is higher for alpha particles than any other, yet the relative penetrating power of alpha radiation is the smallest of the four types of radiation, and alpha radiation is not the most harmful to humans. Why doesn't RBE correspond to how harmful a type of radiation is?

Because it doesn't know how or where the radiation comes from. Your scenario always assumes that it is coming from outside the body, and thus, have to penetrate through the skin. The RBE doesn't account for that. All it does is for 1 kg of tissue, how much damage does each of those cause when compared to the damage done by x-ray.

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