PHYS 1070 Lecture Notes - Lecture 25: Radiant Intensity, Linear Energy Transfer, Electronvolt
11 Apr 2017
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Exposure increases linearly with time > e (p) t. In the distance of shielding, the radiation intensity follows an inverse square law: E (p) 1/r^2 > where r is the distance to the source. A person twice as far from the source receives only 1/4 of the exposure. If possible put something (shielding) between you and the source that absorbs the radiation. The amount and type of shielding required depends strongly on the type of radiation (a, B, y) and the energy of the radiation. A particle are charged (z = +2) particles and lose energy very rapidly in matter through collision with the electrons of the atom. A 5 mev a-particle has a range of ~ 2 cm in air and only ~ 30 um in water. A-particles are very easy to shield, and only of biological concern if ingested or inhaled.
