ENS 52717
ENS Event | |
|---|---|
05:00 Apr 28, 2017 | |
| Title | Agreement State Report - Radiographer Trainee Badge Read Greater than 5 Rem |
| Event Description | On April 29, 2017, the Agency [Texas Department of State Health Services] was notified by the licensee that on April 28, 2017, one of its radiographer trainees had reported their self-reading dosimeter had gone off-scale. The licensee stopped all work and sent the trainee's OSL [Optically Stimulated Luminescence] dosimeter to be processed. The licensee received a verbal report from the processer on April 29, 2017, and the dose was reported as 5.392 REM. The licensee did not know if the dose was static or dynamic. The licensee stated that the trainee had not operated the exposure device and did not know how the trainee could have received the exposure. The licensee stated there was a chance that the dose was to the badge only. The licensee is conducting a formal investigation into the event. No other individual reported an unusual exposure. The exposure device was a QSA 880D camera containing a 51 Ci Ir-192 source. Additional information will be provided as it is received in accordance with SA-300."
Texas Incident No.: I-9482
The following information was received from the State of Texas via email: On May 30, 2017 a detailed report was received by the corporate RSO [Radiation Safety Officer] stating the details of this event. The amount of information was limited and an on-site investigation was conducted on June 7, 2017. By interviewing employees who were at the event, it was determined that the individual did receive the dose of 5.392 REM (whole body) on April 28, 2017 as indicated on his badge reading. He was wearing monitoring devices and an alarming rate meter. There was extreme noise in the area. The exposed employee was a trainee and did not operate the radiography device, although the trainee was experienced in rope repelling in this specific situation and positioned the camera 30 feet above the floor in a pipe rack and collected the film. He did not crank the source in or out. He mounted the camera in the pipes, repelled down the ropes out of the area while the weld was imaged. He returned to the area after the trainer cranked in the source, checked a survey meter on the floor level, 30 feet below the camera, and shielded (there were pipes containing fluids and concrete columns shielding the area), while the trainee climbed the distance to collect the film. The trainee did not take the survey meter with him to do a post exposure survey near the camera or film (the meter is routinely snapped on the harness or cow-tail lanyard, but not this time). He collected the film and lowered it by rope to the trainer. The trainee decided on his own to stay in the rope harness near the camera, unknown to him that the source was slightly exposed. His alarming rate meter may have alarmed although he wouldn't have heard it, nor did he check it. The trainer took the film to the developer in another trailer onsite. When he returned (about 20 minutes) to say, film good, the trainee tried to unhook the cable. When it failed to unhook, another trainer in the crew had seen him and turned the crank handle to fully retract the source (uncertain, about half a turn). The trainee immediately lowered himself to the ground and both went to the vehicle. It was found that his pocket dosimeter was off scale, alarming rate meter was not alarming at this point and trainer phoned the RSO to get advice. Work stopped and the employees stayed on site. The RSO collected badge and sent it for immediate processing and gathered as much information as possible. It is believed the trainee's dose, according to the trainers, was to his whole body and possibly a few seconds to his right hand while trying to disconnect the cable. Within days, the trainee was released from employment from the company and disciplinary action taken against the other trainers. In an attempt to contact the trainee, the trainee responded to a phone text message stating he has not had any redness or tingling in his hand. He also stated he did not touch the collimator. The hand dose is estimated to be less than 2.5 millirem for three seconds or less. Notified R4DO (Rollins), NSIR (Milligan), NMSS (Rivera-Capella), and NMSS Events Notification via email.
The RSO has finally completed and provided a rough calculation of the extremity dose on June 16, 2017. The hand dose was difficult to calculate due to deficiencies in rationale of where the source was in position to the exit port on the camera. The company dose was initially rejected due to rationale that if the whole body dose was 5 rem; how could the extremity dose be smaller. The deficiency in knowing the time, distance and actual source shielding was resulting in varied numbers for the extremity dose. After discussing the situation and calculations with the RSO, it was agreed that the dose be assigned 10 rem to the right hand which is below the 50 rem reportable limit. Notified R4DO (Campbell) and NMSS Events Notification via email. |
| Where | |
|---|---|
| Versa Integrity Houston, Texas (NRC Region 4) | |
| License number: | L06669 |
| Organization: | Texas Dept Of State Health Services |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+38.45 h1.602 days <br />0.229 weeks <br />0.0527 months <br />) | |
| Opened: | Art Tucker 19:27 Apr 29, 2017 |
| NRC Officer: | Bethany Cecere |
| Last Updated: | Jun 16, 2017 |
| 52717 - NRC Website | |
Versa Integrity with Agreement State | |
WEEKMONTHYEARENS 527172017-04-28T05:00:00028 April 2017 05:00:00
[Table view]Agreement State Agreement State Report - Radiographer Trainee Badge Read Greater than 5 Rem 2017-04-28T05:00:00 | |