Plutonium Biokinetics in Human Body A. Luciani - Kit-Bibliothek - FZK

w R is the radiation weighting factor for the radiation type R;
m T (in grams) is the mass of the target organ T.
The total committed equivalent dose to the target organ T from all the source organs S, over
which the introduced radionuclide is distributed, is given by the summation over source organs S:
∑ = k∑U S∑
SEE(T← S) R = k∑ US S R
S R
H T (50) = H(50)(T←S)
S
159
Y R E Rw R AF(T ← S) R
m T
equation A.8
The committed effective dose is calculated on the basis of the committed equivalent dose
analogously to the expression in equation A.4:
E(50)= ∑wTHT(50) T
equation A.9
The ICRP, in the Publication 61, provides an expression to evaluate the committed effective
dose where a way to weight committed equivalent dose for the organs or tissues of the remainder
group is also given:
12
∑
E(50) = wT HT (50) + wremainder T = 1
equation A.10
where T ranging from 1 to 12 represents the main organs of Table A.2, T ranging from 13 to
22 represents the ten remainder organs with tissue weighting factor w remainder = 0.05 and m T is the
respective mass.
In those exceptional cases in which a single one of the remainder tissues or organs receives
an equivalent dose in excess of the highest dose absorbed by any of the twelve main organs or
tissues for which a weighting factor is specified (Table A.2), half of w remainder (0.025) must be
applied to this tissue or organ and half of w remainder to the average dose in the rest of the remainder
organs group. Therefore in such case the committed effective dose must be calculated as:
12
∑
E(50) = wT HT (50) + 0.025
T = 1
22
∑
T =13
equation A.11
where T* relates to the organ or tissue of the remainder group that has the highest
committed equivalent dose in comparison to the main organs or tissues.
22
∑
∑
m T H T (50)
T =13
22
∑ mT T = 13
mT HT (50) − mT*HT*(50) 22
m − m T T*
+ 0.025HT*(50) ∑
T=13