Implementation of a programme for reduction of radiographic doses and results achieved through increases in tube...

Experiences in implementation of a programme to reduce doses to patients from radiographic examinations are described. A preliminary survey of entrance doses for selected examinations, calculated from mean exposure factors, identified equipment and examinations requiring attention. Subsequently more detailed studies were carried out with thermoluminescent dosimeters (TLDs). Results were coordinated with the aid of a database, which was used to monitor the agreement between dose calculations and TLD measurements. Surveys highlighted that doses from lumbar and thoracic spine examinations were high throughout the region. Reductions of 26-36% in entrance dose and 20-25% in effective dose were achieved by raising tube potentials for these examinations. This gave a reduction in annual collective dose of 4 man-Sv with no cost implication. In some departments dose charts were used to support the purchase of new screens. Surveys revealed a wide range in other factors such as transmission of X-ray table tops and results are being used in planning replacement of equipment.