Page 214 - Radiation Safety

Particulate: Beta ( ) and Positron ( )
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  (negatron, e ), positron (e ,  ), emitted when nuclides decay,
continuous energy distribution, avg. E = (1/3) E max

e.g. 32 15 P → 0 -1  + 32 16 S + anti neutrino

 Cause ionisations and excitations in matter, accompanied by X-rays

(bremsstrahlung - increasing with Z), greater range than  , use low-Z

materials (Z<13) as shields

 An external hazard if E > 70 keV (penetrates dead skin layer).

 An internal hazard although not as harmful as alpha

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 Pure  emitters: H, C, Sr, Y, P

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