Harmful tissue reactions caused by killing large numbers of cells, such as skin burns, cataracts, sterility and acute radiation syndrome. Each has a threshold: skin reddening at a few gray, acute radiation syndrome above about 1 Gy to the whole body, and lens opacities at around 0.5 Gy. They are a concern in accidents, radiotherapy and high-dose sources such as radiography, not in normal occupational exposure.
Contact dose rate on that source is high enough for deterministic effects in minutes, tongs only.
Also heard as
- tissue reactions
- non-stochastic effects
Related terms
Stochastic effects
Radiation effects, chiefly cancer, whose probability rises with dose but whose severity does not.
Gray
The SI unit of absorbed dose, equal to one joule of energy deposited per kilogram.
Absorbed dose
The energy deposited by ionising radiation per unit mass of material, measured in gray.
Orphan source
A radioactive source that has escaped regulatory control because it was lost, stolen, abandoned or never licensed.