Supervision of site radiography contractors

Gamma radiography is used extensively under conditions of site radiography for non destructive testing of components where it is not reasonably practicable to check these components in a shielded enclosure. This is one of the few occasions when a high activity radioactive source is used outside a shielded enclosure and administrative controls are the principal means of restricting exposure. A company where site radiography is required should carry out certain checks themselves to ensure that other personnel not involved in the radiography are not exposed to ionizing radiation. Prior discussion with the radiography company on their safety systems and equipment and checks by the client before and during radiography will reduce the likelihood of unintentional exposures and ensure that no radioactive materials are left on the site.