Technologist Radiation Exposures from Nuclear Medicine Imaging Procedures

Radiation exposures incurred by nuclear medicine technologies during diagnostic imaging and scintillation camera quality control were measured in a procedural basis over a 3-mo period using a portable, low range, self-reading ion chamber. A total of more than 400 measurements were made for 15 selected procedures. From these, mean procedural exposures and standard deviations were calculated. The results show that daily flood phantom quality control, at 0.58 mR, and gated cardiac studies at 0.45 mR, were the two greatest sources of exposure. Other procedures resulted in exposures varying roughly from 0.10 to 0.20 mR. Difficult patients were responsible for doubling technologist exposure for many procedures. Standard deviations were large for all procedures, averaging 65% of the mean values. Comparison of technologist exposure inferred from procedural measurements with the time coincident collective dose equivalent recorded by the thermoluminescent dosimetry service of the Bureau of Radiation and Medical Devices, Department of Health and Welfare, Canada, indicates that approximately half of the collective technologist exposure arose from patient handling and camera flood quality control.