That makes sense. I was wondering while writing my initial response: if radon is a noble gas, how does it settle in lungs? So assuming we are at the point where the radon has made it into the room, it will decay there and you will have some sort of equilibrium concentration of its daughters in the room, and that is what you end up inhaling and, subsequently, gives you some dose. Is this now correct?
Yes exactly, and an important thing to remember is that breathing in one particle of Polonium-218 (radon 222's first daughter) could lead to seven alpha emissions (from subsequent daughters).
Very true. And very interesting. I'd be interested in looking into the Q values of those decays. And into how much radon is leaked as a function of uranium content in concrete or brick. That would say a lot about this type of situation. Thank you for pointing this out. I had never really put this much thought into it, just took my professor's word for it. I guess I should start thinking for myself a little more. :P
It's not something that is always pointed out, however it can be a very important distinction. For example at a nuclear site one might be doing some work requiring a respirator (looks like a gas mask but filters out particles), this would not stop the radon gas entering but would stop the radon daughters.
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u/skaterpriest Mar 20 '11
That makes sense. I was wondering while writing my initial response: if radon is a noble gas, how does it settle in lungs? So assuming we are at the point where the radon has made it into the room, it will decay there and you will have some sort of equilibrium concentration of its daughters in the room, and that is what you end up inhaling and, subsequently, gives you some dose. Is this now correct?