Semantic search

Jump to navigation Jump to search
 Start dateReporting criterionTitleEvent descriptionSystemLER
ENS 401418 September 2003 16:30:00Agreement StateAgreement State Report - Iridium 192 Source Failed to RetractThe following was received via fax from the California Radiation Control office: At about 9:30 a.m. on 09-08-03, an Ir-192 source (4.6 Ci (Curie)) failed to retract following a patient treatment. The source became stuck in the transfer tube. The physicist started his stopwatch, entered the room and attempted to manually retract the source. Manual retract failed. The physicist called the physician, who was waiting outside the room. The physician entered the room and disconnected the apparatus from the patient and dropped the transfer tube into a lead pig. The physicist and physician moved the patient out of the room. The physicist stopped the watch and it showed that 2 minutes had elapsed. The physicist surveyed the patient and obtained no measurement above background. The physicist re-entered the room and performed a radiation survey, and found the hot spot along the transfer tube to be in the pig. The pig measured 10 mR (millirem) /hr at 3 feet. The room was locked and posted until arrival of the manufacturer's representative, who also was unable to make the source retract. The manufacturer's representative placed the transfer tube into a shipping container and shipped it back to the manufacturer for further investigation. Doses to the patient, physicist and physician were estimated as follows: patient skin dose (10cm from source for 2 minutes) = 9 rem; physicist for 2 minutes = 45 mrem (millirem); physician 125 mrem (millirem) whole body and 15 rem extremity. The device used was a Nucleotron MicroSelectron HDR (High Dose Rate) model number 31324 (Serial Number D36A4476). The malfunction of the device is under investigation.