Ionising radiations: precautions for industrial users.

  • Great Britain. Department of Employment and Productivity.
Date:
1969
Catalogue details

Licence: Public Domain Mark

Credit: Ionising radiations: precautions for industrial users. Source: Wellcome Collection.

    10/76 (page 8)
    BETA PARTICLES These are streams of fast moving electrons. Beta particles are some- what more penetrating than alpha particles but although not pene- trating much deeper than the skin can cause burns, radiological dermatitis, dryness and cracking of the nails and skin, and wart formations which may develop into skin cancer. The eyes can be affected by beta particles, and prolonged excessive exposure to the more energetic particles may lead to cataract formation. Inhalation or ingestion of beta emitters can similarly lead to internal tissue and blood cell damage. GAMMA AND X-RADIATION AND BREMSSTRAHLUNG Gamma and X-radiation are penetrating electro-magnetic radiations. Bremsstrahlung is a type of electro-magnetic radiation produced when beta particles are slowed down, especially when passing through materials of high atomic number. The energy of the bremsstrahlung will depend upon the energy spectrum of the beta particles. The effects of gamma and X-rays and bremsstrahlung are essenti- ally similar. Since these rays can pass through the body without appreciable attenuation, except in the case of low energy X-rays, they can irradiate the blood-forming organs and so cause changes similar to those produced by alpha emitters in the body, namely, anaemia and leucopenia, and they may also induce leukaemia. They can cause bad skin burns and other skin effects similar to those caused by beta particles. Because X-ray beams are often much more concentrated and intense than gamma ray beams, particular care is needed to guard against skin burns. There is the possibility of producing impaired fertility or temporary sterility, though not impotence, from exposure of the gonads to excessive amounts of radiation. Finally, there are possibilities that excessive radiation may produce deleterious genetic effects. It is important, therefore, to ensure that the irradiation of persons of reproductive capacity is kept within the maximum permissible levels. NEUTRONS These are particles having no electric charge. They are very penetrat- ing and produce ionisation by secondary action. Neutrons in the region of 1 MeV and above are called fast neutrons. Those which have been slowed right down and are in thermal equilibrium with their surroundings have an energy of about 0-025 eV and are called