About 10 years ago, NRC inspectors uncovered violations of fire protection requirements at many plants. Some plant owners did not physically separate the electrical cables for safety systems and their backups, which meant that a fire could destroy both sets of cables. They relied on operator manual actions to save the day—operators would race to the far end of fire-damaged cables and manually start or stop equipment as needed to cool the reactor core. Because these operator manual actions had not been formally reviewed and approved by the NRC, they were illegal.In June 2011, the NRC released a report on its evaluation of safety problems caused by the lack of a different kind of manual actions. The “manual” this time refers to the manuals supplied by vendors with safety equipment installed at nuclear plants.
The vendor manuals contain instructions on how to install, operate, test, and maintain safety equipment. But like directions in a recipe, these instructions are only successful when followed. The NRC’s evaluation concluded that many safety problems are caused by workers not following the vendor’s guidance. Between 2008 and 2010, the NRC found that manual inactions:
- caused 40 safety system failures
- caused 15 reactor shut downs
- triggered 2 nuclear plant emergencies
- resulted in 45-50 NRC inspection findings each year
- factored in approximately 30 percent of risk significant safety violations
The NRC was justifiably concerned that not following vendor recommendations could lead to the common-cause failure of an entire array of emergency components. For example, if pumps are not properly lubricated, they could all be disabled by overheated bearings.
The NRC concluded:
While there appears to be no distinguishable upward trend, the consistent number of findings year to year, combined with the number of significant events related to ineffective use of vendor recommendations, indicates a real opportunity for licensees to improve their programs and reduce their vulnerability so such events.
This NRC evaluation report is available online.
Our Takeaway
First, the NRC did a good job connecting the dots on this issue. It stepped back to see the big picture painted by numerous findings.
Second, there are ample safety and economic grounds for the nuclear industry to more effectively implement vendor recommendations.
Third, reading is fundamental. If the reason owners have not implemented vendor recommendations is that they have not read the vendor manuals, there’s a good chance they won’t read the NRC’s evaluation either.
In that case, maybe they’ll read the tickets the NRC should write for the next safety violations caused by manual inaction.
“Fission Stories” is a weekly feature by Dave Lochbaum. For more information on nuclear power safety, see the nuclear safety section of UCS’s website and our interactive map, the Nuclear Power Information Tracker.