STAFF RADIATION-DOSES DURING 8 YEARS IN A NUCLEAR-MEDICINE RADIOPHARMACY

It is important that staff radiation doses be kept 'as low as reasonab ly achievable' (ALARA). Staff working in the radiopharmacy and nursing staff responsible for injecting radionuclides are being monitored con stantly in our department. We report here on the effective doses and d oses to the hands received by staff at two hospitals during 8 years fr om January 1985 to December 1992. In addition to the doses determined monthly by the South African Bureau of Standards' Radiation Protection Service (SABS), radiation doses received to the hands and whole body were measured every week using lithium fluoride thermoluminescent dosi metry (TLD). The workload (number of patient studies each year) and th e estimated amount of Tc-99m received per month were also established, and results have been expressed in relation to these where possible. The combined radiation doses and the absorbed dose per unit activity a single radiographer would have received, since 1988 when radiopharmac y duties were centralized, were calculated. The highest total radiatio n dose received in any one year by any one person at hospital A was 22 3.53 mSv to the hands, and 10.20 mSv and 8.37 mSv to the whole body de pending on the dosemeter used. The corresponding values for hospital B were 54.05 mSv to the hands and 6.94 mSv and 4.43 mSv to the whole bo dy. If only one radiographer should do all the work the calculated hig hest dose received would be 447.06 mSv to the hands and 9.68 mSv SABS effective dose. The radiation doses to staff were well within the limi ts prescribed; this is attributed to the practice of maintaining a hig h awareness of radiation safety and meticulous training and rotation o f staff in the radiopharmacy.