The following information was received via email from the state of North Dakota:
Desert NDT, LLC dba Shawcor reported a 3.256 TBq (88 Ci) Iridium-192 sealed source (Industrial Nuclear Model 32, serial #022E) had disconnected from a drive cable connected to an Industrial Nuclear Model IR-100 radiography exposure device (serial #4321) at a temporary job site in Williston, ND on 2/12/2019. The event occurred at 1645 [MST] while the radiography crew, consisting of a radiographer and assistant radiographer, was performing industrial radiography under extreme cold weather conditions on a pipe section. Upon retracting the source after the third exposure, the crew noticed the radiography device's safety latch did not pop up indicating the source in the safe/locked position. Upon performing a radiation survey while approaching the device, the crew noticed an increased exposure rate indicating a source disconnect. The crew immediately retreated from the device and reset an actual 2 mR/hr public dose boundary and contacted their radiation safety officer who made arrangements for authorized retrieval personnel to dispatch to the site. The crew maintained constant surveillance of the site while awaiting the source retrieval personnel. The source was successfully retrieved at 2020 [MST]. At the time of the event, the radiographer had received 50 mR and the assistant radiographer 55 mR on their direct reading dosimeters. The retrieval individual received a total of 357 mR to the direct reading dosimeter located on his arm and 243 mR to the direct reading dosimeter located on his chest. Shawcor will provide a detailed report to the North Dakota Department of Health upon establishing the root cause and corrective actions.
NMED Item #ND190001