The absorbed dose in a tissue or organ multiplied by a radiation weighting factor that reflects how damaging each type is: 1 for photons and electrons, 20 for alpha particles, and between about 2.5 and 20 for neutrons depending on energy. Expressed in sieverts, it is used for organ-specific limits such as the lens of the eye, skin and extremities. A gray of alpha to the lung therefore counts as 20 Sv equivalent dose.
Extremity equivalent dose for the valve job is projected at 120 millisievert to the hands, rings on both.
Also heard as
- organ equivalent dose
- HT
Related terms
Absorbed dose
The energy deposited by ionising radiation per unit mass of material, measured in gray.
Effective dose
A whole-body dose figure that adds up organ doses weighted by each tissue's sensitivity to radiation risk.
Sievert
The SI unit for equivalent and effective dose, used to express radiation risk to people.
Hot particle
A tiny, highly radioactive fragment that can deliver a large localised skin dose if it lands on someone.