ENS 44344
ENS Event | |
|---|---|
15:30 Jul 11, 2008 | |
| Title | Item Relied on for Safety Discovered Inoperable |
| Event Description | NOX (nitrogen dioxide, nitric oxide, etc) detection is IROFS [Item Relied On For Safety] BPF-43 for the BPF facility. This IROFS is one of the two controls used to prevent chemical occupational exposure to NOX emissions due to the U-Aluminum Bowl Cleaning operations. 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 24, 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).
The other IROFS credited in the ISA Summary for this accident is BUA-43, (power is automatically removed from caustic pumps securing sodium hydroxide flow to U-Aluminum dissolvers upon low sodium nitrate flow as detected by flow switches). From late May until early July of 2008, these flow switches were not functioning correctly, so written and approved compensatory measures were implemented. However, per NFS procedure, these temporary compensatory measures were not incorporated into the ISA Summary so were not available to help meet the performance criteria of 10 CFR 70.61. Since IROFS BPF-43 was in a degraded condition during this time period, performance criteria were not met. The licensee has ceased operations in the affected building. The functional test performed in January 2008 utilized the out-of-date calibration gas. The functional test previous to the functional test performed in January 2008 was performed in July 2007. The licensee has had no indication or evidence that NOX emissions occurred during the degraded condition period. The licensee is investigating this incident to determine further controls required to prevent reoccurrence. The licensee has notified the NRC Resident Inspector.
The licensee is retracting this report based on the following: On July 11, 2008, NFS made a 24-hour report (NRC Event No. 44344) 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 BPF-43 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 BPF-43, 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:+0.4 h0.0167 days <br />0.00238 weeks <br />5.4792e-4 months <br />) | |
| Opened: | Mike Tester 15:54 Jul 11, 2008 |
| NRC Officer: | Donald Norwood |
| Last Updated: | Aug 5, 2008 |
| 44344 - 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 | |