A study on occupational exposure in a PET/CT facility.

Abstract

Staff occupational exposure for (18)F-FDG studies has been assessed. For this purpose, different detectors, all traceable to PTB standards, have been used. Measurements were carried out in different working areas in the facility for different procedures and 400 MBq per patient standard injected activity. A radiological map of the patient lying on the couch was obtained; the largest dose rate result was obtained in contact with the patient's abdomen. The maximum dose to the most exposed staff member for this position is 3.6 mSv y(-1), under some conservative assumptions. A typical value would be 0.9 ± 0.3 mSv y(-1) close to the abdomen, taking into account staff rotations. These results have been obtained from a sample of 50 patients and average values have been statistically tested. Particularly, a negligible probability of reaching 20 mSv in a year (assuming no incidents or contamination) was obtained (P < 0.01). Annual dose received by personnel lies well within the recommended limits (International Commission on Radiological Protection), these measurements help to optimise working procedures in the facility.