This is the measure that indicates the degree of biological damage caused by radiation. Equivalent dose is measured in rems. [Back to Module 2
(previously "Dose Equivalent") The International Commission for Radiological Protection's term (starting with ICRP Publication 60) for the product of the amount of energy absorbed per mass of tissue (joules per kilogram) times the quality factor for the type of radiation imparting the energy. The unit used for equivalent dose is the sievert (Sv). The unit used previously for dose equivalent was the rem. (1 rem = 0.01Sv)
A quantity developed for purposes of radiation protection and assessing risks to human health in general terms, defined as the average absorbed dose in an organ or tissue modified by the radiation weighting factor for the type, and sometimes energy, of the radiation causing the dose, as defined in ICRP (1991a). Supersedes average dose equivalent, as defined in ICRP (1977). The SI unit of equivalent dose is the joule per kilogram (J kg−1), and its special name is the sievert (Sv). In conventional units used in this report, equivalent dose is given in rem; 1 rem = 0.01 Sv.
A quantity obtained by multiplying the absorbed dose by a radiation-weighting factor to allow for the different effectiveness of the various types of ionizing radiations in causing late effect harm in tissue. The equivalent dose is theoretical and has replaced the earlier dose equivalent. The equivalent dose is often expressed in sievert (Sv). It is also sometimes expressed in rem (an older unit). One hundred rem equals 1 Sv.
The equivalent dose is a measure of how the absorbed dose (energy) deposited in tissue affects humans. Since not all types of radiation produce the same effect in humans the equivalent dose takes into account the type of radiation, using a quality factor that is based on the biological effect of the radiation type, and the absorbed dose. For example, when considering beta, x-ray, and gamma-ray radiation, the equivalent dose (expressed in rems) is equal to the absorbed dose (expressed in rads). For alpha radiation, the equivalent dose is assumed to be twenty times the absorbed dose.
The equivalent dose is a measure of the effect which radiation has on humans. The concept of equivalent dose involves the impact that different types of radiation have on humans. Not all types of radiation produce the same effect in humans. The equivalent dose takes into account the type of radiation and the absorbed dose. For example when considering beta, x-ray, and gamma ray radiation, the equivalent dose (expressed in sieverts or rems) is equal to the absorbed dose (expressed in grays or rads). For alpha radiation, the equivalent dose is assumed to be twenty times the absorbed dose.
A quantity used for radiation-protection purposes that takes into account the different probability of effects which occur with the same absorbed dose delivered by radiations with different W values. It is defined as the product of the averaged absorbed dose in a specified organ or tissue (DT) and the radiation weighting factor (W) values. If dose is in gray (Gy), equivalent dose is in sieverts (Sv).
The quantity obtained by multiplying the absorbed dose by a factor to allow for the different effectiveness of the various ionising radiations in causing harm to tissue. Unit sievert, symbol Sv.
The equivalent dose (HT) is a measure of the radiation dose to tissue where an attempt has been made to allow for the different relative biological effect of different types of ionizing radiation. Equivalent dose is therefore a less fundamental quantity than radiation absorbed dose, but is more biologically significant. Equivalent dose has units of sieverts.
