ENS 51761
ENS Event | |
|---|---|
06:00 Feb 29, 2016 | |
| Title | Agreement State - Stuck Shutter in the Normally Open Position |
| Event Description | The following Agreement State Report was received from the State of Texas via email:
On March 1, 2016, the Agency [Texas Department of State Health Services] received notice that on February 29, 2016, the licensee had discovered that a Berthold fixed gauge model MB7442D containing 30 milliCuries of cesium-137 had malfunctioned. The shutter was stuck in the open position. The gauge is normally left in the open position, and no exposure to the public is likely. Additional information will be provided as it is received in accordance with SA-300. Texas Incident #: I 9383
The following updated report was received from the State of Texas via facsimile: The following information was provided by the manufacturer: Celanese of Bishop, TX contacted Berthold in early March [2016], to come out and repair a LB 7442 device with a broke shutter. This device was one of many that was sold by BSI until they went out of business in [approximately] 2003. The cause of the broke shutter was corrosion that had built up on the brass shutter shaft making it hard to turn. When the Berthold service engineer was replacing the shaft he noticed that the source holder did not have a lock washer between the source holder and the source. The missing lock washer was not the cause of the broke shutter but has been an issue in the past with a plant in Wyoming that had some of the older BSI devices. Vibration caused the source to come lose from the source holder, the source dropped down into a position that prevented the shutter mechanism from cutting off the radiation beam when rotated which resulted in continuous high readings. Berthold worked with the NRC and the Wyoming plant to inspect the remaining shields to see if there were others that were missing the lock washer. It was noted that some did in fact have the lock washer in place but some did not. The sources that did not have lock washers on them were disassembled from their source holder and lock washers were added. [The manufacturer has] not seen any other records of this happening except for the FMC Corp plant in Wyoming in 2010. At Celanese, the Berthold service engineer removed the source from the source holder and added a lock washer before placing it back into the shield. It was noted by the Berthold service engineer that Celanese appeared to have more of the same devices from that era. The issue in Wyoming could have been an isolated incident but definitely worth noting. Notified R4DO (Kellar) and NMSS Events Notification. |
| Where | |
|---|---|
| Ticona Polymers Inc Bishop, Texas (NRC Region 4) | |
| License number: | 02441 |
| Organization: | Texas Dept Of State Health Services |
| Reporting | |
| Agreement State | |
| Time - Person (Reporting Time:+31.37 h1.307 days <br />0.187 weeks <br />0.043 months <br />) | |
| Opened: | Gentry Hearn 13:22 Mar 1, 2016 |
| NRC Officer: | Steven Vitto |
| Last Updated: | Apr 8, 2016 |
| 51761 - NRC Website | |
Ticona Polymers Inc with Agreement State | |
WEEKMONTHYEARENS 525952017-03-07T00:30:0007 March 2017 00:30:00
[Table view]Agreement State Agreement State Report - Stuck Shutter Device ENS 517612016-02-29T06:00:00029 February 2016 06:00:00 Agreement State Agreement State - Stuck Shutter in the Normally Open Position ENS 473812011-10-13T12:00:00013 October 2011 12:00:00 Agreement State Agreement State Report - Broken Handle on Berthold Nuclear Gauge ENS 467332011-04-06T05:00:0006 April 2011 05:00:00 Agreement State Agreement State Report - Stuck Shutter on Ohmart Model Sh-F1 Gauge 2017-03-07T00:30:00 | |