Reducing exposure to radiation ...
In this section we will look at the methods of reducing exposure to radiation and the types of shielding required.
Sources of external radiation
The external radiation hazard is due to sources of ionising radiation which are external to the body whereas an internal radiation hazard is where the radioactive material has entered the body. It is most important to understand the difference between radiation hazard and contamination hazard. The external radiation hazard can be due to beta particles, gamma and x-rays and neutrons. Alpha particles are not an external radiation hazard because they are easily stopped by the outer layers of skin and only travel a few centimetres in air.