However within the US NRC system " dose equivalent " is still used to name quantities which are calculated with tissue and radiation weighting factors, which in the ICRP system are now known as the " protection quantities " which are called " effective dose " and " equivalent dose ".
32.
Confusion between US and ICRP dose quantity systems can arise because the use of the term " dose equivalent " has been used within the ICRP system since 1991 only for quantities calculated using the value of Q ( Linear energy transfer-LET ), which the ICRP calls " operational quantities ".
33.
However, the absorbed dose and dose equivalent for a Mars mission were predicted in the early 1990's by Badhwar, Cucinotta, and others ( see for example Badhwar, Cucinotta et al ., Radiation Research vol . 138, 201-208, 1994 ) and the result of the MSL experiment are to a large extent consistent with these earlier predictions.
34.
Although the CIPM definition states that the linear energy transfer function ( Q ) of the ICRU is used in calculating the biological effect, the ICRP in 1990 developed the " protection " dose quantities " effective " and " equivalent " dose which are calculated from more complex computational models and are distinguished by not having the phrase " dose equivalent " in their name.
35.
"The calculation of the committed effective dose equivalent ( CEDE ) begins with the determination of the equivalent dose, H T, to a tissue or organ, T . Where D T, R is the absorbed dose in rads ( one gray, an SI unit, equals 100 rads ) averaged over the tissue or organ, T, due to radiation type, R, and W R is the radiation weighting factor.
