THE SAFE MANIPULATION OF 2,000 CURIES OF COBALT-60 IN A TEMPORARY ENCLOSURE

The method used in the transfer of a 2,000-c Co/sup 60/ source from its shipping cask to a radiation therapy unit at Preroria, South Africa, General Hospital is given. The method entailed the construction of a shield to protect the personnel during the transfer and a viewing system to observe the transfer procedure. The shield consisted of 3.5-ft front and 12-in. side walls made from 6 by 6 in. concrete blocks; there was no shielding across the top of the enclosure. Two viewing systems were installed: (1) three mirrors serving effectively as a periscope and (2) a closed-circuit television system. The transfer operation took 20 minutes, and the total exposure dose received by operating personnel was 45 mr. (B.O.G.)