Code of practice for the protection of persons exposed to ionizing radiations / [prepared by the Standing Advisory Committee].

  • Great Britain. Radioactive Substances Advisory Committee.
Date:
1957
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Licence: Public Domain Mark

Credit: Code of practice for the protection of persons exposed to ionizing radiations / [prepared by the Standing Advisory Committee]. Source: Wellcome Collection.

    13/92 (page 7)
    4.3. The amount of ionizing radiation received by personnel employed in these departments should be systematically checked! to ensure that the maximum permissible doses and the permissible cumulative doses? for the various types of external radiation involved are not exceeded. For the purpose, ionization chambers or film badges should be carried on the person. No single test should extend beyond a period of four weeks. The monitcring should be continuous and a personal cumulative record should be kept of the doses of radiation received, not only occupationally but also from all other sources such as personal examination by means of diagnostic radiology. 4.4. Provided that radiation monitoring (both site monitoring and personnel monitoring) is carried out in all circumstances involving occupational exposure to penetrating ionizing radiations, then: (a) routine blood counts are unnecessary in the case of workers who receive average doses not exceeding one-half of the maximum permissible weekly level averaged over a period of three months; and (b) routine blood counts are desirable in the case of workers who receive average doses exceeding one-half of the maximum permissible weekly level averaged over a period of three months. The blood counts should be carried out periodically, at intervals of not longer than three months. These rules are a simplification of those recommended by the International Commission on Radiological Protection. 4.5. If personnel tests indicate that doses in excess of the permissible levels are being received, an inspection of the department should be made by a qualified expert to determine the cause (e.g. defective equipment, inadequate protection afforded by screens or walls, wrong technique, or insufficient staff). The expert should indicate the measures to be adopted to rectify the situation. 4.6. In the case of staff in rooms adjacent to, and above, and below, X-ray and -ray rooms, personnel monitoring and medical examination are not necessary, if the weekly dose can never exceed one-tenth of the maximum permissible weekly dose for those occupationally exposed. 1 Personnel monitoring tests will be undertaken by hospital physicists associated with major hospitals or by the Radiological Protection Service. 2 See Section 6 of the Supplement.