Radiation protection requirements for a whole-body CT scanner

Exposure values for a whole-body CT scanner, obtained from a room protection survey covering one month (119 patients), are reported. It was found that weekly exposures could be expected to be in the range of 350-750 mR/week for a daily load of 12 patients. The h.v.l. of gypsum board, lead, and plate glass at this radiation level was 1.8, 0.020, and 1.3 cm, respectively. The authors suggest that plate glass is not the method of choice for shielding a high-volume body scanner installation unless a large enough lead glass window is not available or cannot be installed in time to meet construction deadlines.