ENS 44345
ENS Event | |
|---|---|
12:30 Jul 14, 2008 | |
| Title | Item Relied on for Safety (Irofs) Discovered Inoperable |
| Event Description | NOX (nitrogen dioxide, nitric oxide, etc) detection is IROFS BUND-17 for the LEU [Low Enriched Uranium] portion of the BPF facility. This IROFS is one of the two controls used to prevent chemical occupational exposure to NOX emissions due to the U-natural dissolution operation. The NOX detector alarms prior to exceeding 5 ppm NOX to allow operations to perform monitoring and/or evacuation actions. On July 11, 2008, it was identified that the calibration gas used to functionally test the NOX detector has expired. The calibration expiration date was September 2007. The prior functional test of the NOX detector was performed on January 11, 2008. Due to use of expired calibration gas, it was determined that the NOX detector (IROFS BPF-43) has been in a degraded condition since the last functional test (January 2008).
A 2nd IROFS is credited in the NOX accident sequence but, with degradation of IROFS BUND-17, the performance criteria of 10 CFR 70.61 were not met. No actual emissions have been identified. The event occurred due to a degraded management measure, specifically a periodic function test. Improved calibration verifications have recently been implemented; this improved check identified the problem of the expired calibration gas. The licensee notified the NRC Resident Inspector.
The licensee is retracting this report based on the following: On July 14, 2008, NFS made a 24-hour report (NRC Event 44345) to the operations center based on 10CFR70, Appendix A, Paragraph (a)(2). 10CFR70, Appendix A, Paragraph (a)(2) requires a 24-hour report for loss or degradation of an item relied on for safety (IROFS) that results in failure to meet the performance requirement of Sec. 70.61. The report was made due to expired calibration gas being used to functionally test the IROFS BUND-17 Nox (nitrogen dioxide, nitric oxide, etc) detector. After calibrating the detector with in-date calibration gas, it was determined that the NOX detector was actually set to alarm at a much more conservative part per million reading than the normal alarm setting. Therefore there was no degradation of the IROFS BUND-17, but rather an increased level of protection had been applied since the last functional test in January 2008. Based on this information, it is requested that this event report be retracted. Notified R2DO (Hooper), NMSS (Tschiltz) and Fuels OUO Gp via email. |
| Where | |
|---|---|
| Nuclear Fuel Services Inc. Erwin, Tennessee (NRC Region 2) | |
| License number: | SNM-124 |
| Reporting | |
| Other Unspec Reqmnt | |
| Time - Person (Reporting Time:+1.45 h0.0604 days <br />0.00863 weeks <br />0.00199 months <br />) | |
| Opened: | Mike Tester 13:57 Jul 14, 2008 |
| NRC Officer: | Mark Abramovitz |
| Last Updated: | Aug 5, 2008 |
| 44345 - NRC Website | |
Nuclear Fuel Services Inc. with Other Unspec Reqmnt | |
WEEKMONTHYEARENS 443452008-07-14T12:30:00014 July 2008 12:30:00
[Table view]Other Unspec Reqmnt Item Relied on for Safety (Irofs) Discovered Inoperable ENS 443442008-07-11T15:30:00011 July 2008 15:30:00 Other Unspec Reqmnt Item Relied on for Safety Discovered Inoperable ENS 410972004-10-06T13:10:0006 October 2004 13:10:00 Other Unspec Reqmnt
2008-07-14T12:30:00 | |