Equipment design:

Till 1992, 80 per cent of radiography cameras were manually operated and were handled by the operator at close proximity resulting in high individual doses. Probability of accidental conditions with manually operated cameras is quite high particularly loss of source leading to excessive exposure to the public at large. Such potential points of exposure has been taken care by withdrawal of manually operated cameras and introduction of remote operated cameras. Under normal working conditions, individual doses are reduced substantially which are highlighted in this paper.

Personnel training:

Total safety is achieved by built-in safety combined with effective administrative control. Work practice has a direct bearing on occupational exposure. Safety awareness programmes contribute a lot in effective management of radiography sites. Training programmes at different levels (operator, site incharge and radiation safety officer) are regularly conducted. Refresher programmes and revalidation of certificates are conducted periodically to monitor the degree of awareness of occupational workers and also to familiarise them and update their knowledge with latest trends in radiation equipment and safety. Before 1977 there was no regular certification programme in this field. Continuous upgradation of training programmes since then has resulted in substantial reduction in individual and collective doses. Impact of training on reduction in dose has been analysed in this paper.

A study is conducted on few selected institutions to see the combined effect of design improvement and training. Study shows that over a period of time, occupational exposure has reduced progressively. An effort was made to resolve the contribution of each of these factors in dose reduction. The results are reported in this paper.