ENS 50453
ENS Event | |
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15:30 Sep 12, 2014 | |
Title | Fixed Gauge Shutter Stuck in Closed Position |
Event Description | The licensee RSO (Radiation Safety Officer) reported that the shutter on a fixed gauge was stuck in the closed position. An authorized technician was able to repair the shutter and the gauge has been returned to service. There were no exposures involved with this event. The gauge is an ABB/IRMS, source model S18 containing a Y-90 300 mCi source. This report is being made per 10CFR30.50(b)(2)(i).
The licensee RSO reported that around 0000 EDT on 9/13/14, an electrician performing routine checks found the gauge shutter stuck in the open position. The technician who performed maintenance on the previous day had caused the shutter to stick in the open position because of a mis-positioned screw. Repairs were completed and the gauge shutter is now functioning normally. This gauge is scheduled to be replaced during the upcoming Christmas shutdown. There were no exposures involved with this event. Notified R1DO (Jackson) and FSME Events Resource via email.
The following report was received from the Novelis Corporation RSO via email; This email serves as [the licensee's] formal notification to follow up the two telephone notifications made by [the licensee's RSO] on September 12, 2014. Both occurrences were related to shutter failures on the same thickness gauge. These notifications were made to satisfy the NRC Regulation 10 CFR 30.50 reporting requirement. On Friday, September 12, 2014, at approximately 1300 [EDT], the shutter on the Novelis Fairmont #1 Mill thickness gauge failed in the closed position. An employee who has received non-routine maintenance training per NUREG-1556, Volume 4, Appendix G & N, took it upon himself to remove the side of the gauge and perform an investigation and repair the stuck shutter. It was determined that the pneumatic cylinder for the shutter was not functioning properly and replaced. A radiation survey was performed and the surrounding area was taped off with caution tape. There was no over exposure to radiation. The gauge was put back into service at approximately 1400 [EDT] that same afternoon. On the same night, Friday, September 12, 2014, at approximately 2330 [EDT], the shutter on the same thickness gauge failed again. This time the shutter failed in the open position. Once the shutter was determined to be in the open position, the foreman on shift notified [the RSO]. [The RSO] spoke with the shift electrician and had him perform a radiation survey and tape off the area with caution tape. The shift electrician has received non-routine maintenance training per NUREG-1556, Volume 4, Appendix G & N. [The RSO] was on site at approximately 0030 [EDT] Saturday morning, September 13, 2014. [The RSO] verified that the shutter was in the open position by performing a radiation survey. Additionally, the light identifying the shutter position was RED indicating the shutter was open. The same individual that replaced the pneumatic cylinder was on site and he investigated the failure. It was determined that the shutter appeared to be on a bind and the screws that hold the pneumatic cylinder in place were adjusted and the shutter was free to move as intended. With the side off of the gauge, next to the shutter assembly, at 6 inches, the measured mR/H was approximately 1 mR/h. Directly beside the shutter mechanism approximately 2 mR/h was measured. The employee worked for about 30 minutes to adjust the shutter mechanism. During this repair, there was no over exposure to radiation. Notified R1DO (Lilliendahl) and FSME Events Resource via email. |
Where | |
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Novelis Fairmont, West Virginia (NRC Region 1) | |
License number: | 47-13348-02 |
Organization: | Novelis |
Reporting | |
10 CFR 30.50(b)(2), Licensed Material Protection Equipment Failure | |
Time - Person (Reporting Time:+1 h0.0417 days <br />0.00595 weeks <br />0.00137 months <br />) | |
Opened: | Michael Rossana 16:30 Sep 12, 2014 |
NRC Officer: | John Shoemaker |
Last Updated: | Sep 15, 2014 |
50453 - NRC Website | |
Novelis with 10 CFR 30.50(b)(2) | |
WEEKMONTHYEARENS 507282015-01-09T05:00:0009 January 2015 05:00:00
[Table view]10 CFR 30.50(b)(2) Gauge Shutter Operated Slowly in the Close Direction ENS 504532014-09-12T15:30:00012 September 2014 15:30:00 10 CFR 30.50(b)(2) Fixed Gauge Shutter Stuck in Closed Position 2015-01-09T05:00:00 | |