The licensee reported their irradiator had a 13 kCi
Co-60 source stuck in the exposure cell. The remote area monitor registered a reading of 70 mR/hr for the area near the source. No personnel radiation exposure occurred. The irradiator building was vacated and an exterior barrier was positioned so personnel exposure would be limited to <2mR/hr. The source is from
MDS Nordion, C132 - Type 72.
The irradiator is a panoramic, dry-source storage which uses pneumatic air as the driving force. The licensee, who had just completed maintenance on the device, was conducting operational tests when the source stuck. The source, which is lodged in the exposure head inside the exposure cell, is prevented from being retracted by a piece of metal called a "head switch". The licensee unsuccessfully tried to free the source by applying high pressure air. The next step the licensee is considering is the possible use of a robot.