Resolution of Generic Safety Issues: Resolution of Generic Safety Issues: NMSS-0019. Control Unit Failures of Classic Nucletron HDR Units ( NUREG-0933, Main Report with Supplements 1–35 )

DESCRIPTION

Several control unit failures in Nucletron Classic Model HDR units occurred over the span of three years: two were reported in 1997; four in 1998; and three in 1999. These nine control unit failures indicated an ongoing problem with unexplained control unit failures. Nucletron continued to investigate the ongoing control unit failures and believes it found the root cause of the failures and subsequently developed appropriate corrective measures. Affected licensees were to be informed and any necessary additional actions were to be taken to ensure that safety was maintained.

CONCLUSION

This issue¹⁷⁸⁰ was resolved with the issuance of Information Notice 99-23.¹⁷⁸³ Additional follow-up with Nucletron on their corrective measures was deemed unnecessary following an analysis of the failures that deemed them to be of low safety significance.

REFERENCES

1780. Memorandum for F. Eltawila from D. Cool, "Submittal of Generic Issues for Tracking in the Generic Issue Management Control System (GIMCS)," November 14, 2000. [ML003763127] 1783. Information Notice 99-23, "Safety Concerns Related to Repeated Control Unit Failures of the Nucletron Classic Model High-Dose-Rate Remote Afterloading Brachytherapy Devices," U.S. Nuclear Regulatory Commission, July 6, 1999. [ML031040399]