Slide 16
Quality Factor
The quality factor for each type of radiation is shown below:
From this it can be seen that alpha radiation is the most ionising radiation out of the three types.
Slide 17
The DOSE EQUIVALENT is a measure of the biological effect of radiation and it takes account of the type and energy of the radiation as well as how the radiation is distributed.
REMEMBER, the biological effect of radiation depends on:
The type of radiation.
The type of body tissue or body organ that absorbs the radiation.
The total amount of energy absorbed.
Slide 18
Because 1 Sv is a very large dose of radiation which could only happen as a result of a very serious nuclear accident or explosion, doses are given in millisieverts (mSv) or microsieverts ( Sv).
The DOSE EQUIVALENT is measured in sieverts (Sv).
Slide 19
Suppose that 100 people all receive a dose equivalent of 1 Sv spread over the whole body. It is estimated that, of the 100 people on average 4 of them would eventually die as a result of the radiation.
But precisely who would die, or when they would die, or what illness they would die of, cannot be predicted.
Slide 20
Radiation is all around us!
Background radiation is radiation that is naturally occurring.
Slide 21
Natural Sources of Radiation
Slide 22
Man-Made Sources of Radiation
Slide 23
Death Risk - Cause