ML16222A852

Human Performance in Operating Events

ML16222A852
Person / Time
Issue date:	03/19/1993
From:	Shewmon P Advisory Committee on Reactor Safeguards
To:	Selin I Advisory Committee on Reactor Safeguards
References
D930319
Download: ML16222A852 (3)

Text

D930319 The Honorable Ivan Selin Chairman U.S. Nuclear Regulatory Commission Washington, D.C. 20555

SUBJECT:

HUMAN PERFORMANCE IN OPERATING EVENTS During the 391st meeting of the Advisory Committee on Reactor Safeguards, November 5-7, 1992, we discussed with representatives of the Office for Analysis and Evaluation of Operational Data (AEOD) a draft of the AEOD study entitled, "Operating Experience Feedback Report - Human Performance in Operating Events." (This study was issued as NUREG-1275 in December 1992.) Representatives of NUMARC provided comments on the draft of this study during our meeting. We also discussed this matter during our 395th meeting, March 11-12, 1993. We had the benefit of the documents referenced.

This study was conducted over a 2 1/2-year period and involved 16 onsite visits by multidisciplinary teams led by an AEOD staff member for the purpose of evaluating human performance during selected nuclear power plant events. The study focused on factors that influenced operator performance during a wide variety of plant events. AEOD estimates that these events represent approximately 30 percent of the events that challenged operating crews during this 2 1/2-year period. The study summarizes each event and the findings that the teams made, provides observations discerned from related events, and presents conclusions concerning overall human performance. These conclusions fall into four categories of human performance issues: control room organization, procedures, human-machine interface, and industry initiatives. Finally, the study attempts to compare the "latent factors" among these 16 events.

Five of the 16 events studied were also the subject of Augmented Inspection Teams (AITs). We believe that a number of the remaining 11 events were of sufficient significance from a human and organizational performance point of view to have warranted an AIT effort. During our meeting with the AEOD staff we commented that the final version of the study should address this issue, since it may be a weakness in the approach being used by the Office of Nuclear Reactor Regulation (NRR) and the Regional Offices in systematically analyzing and evaluating human performance in operating events. AEOD did not explicitly deal with this issue in the final version of the study.

We have been critical of AEOD in the past for its reluctance to discuss the performance of NRC staff organizations in the course of carrying out studies of this nature. It continues to be our view, as discussed under Summary and Conclusions below, that this should be a necessary part of AEOD studies of this nature.

The Analysis section of the study (Section 3.0) contains a number of observations and conclusions that we believe are of importance from a nuclear safety perspective. We have the following comments on this section of the study:

Control room organizational weaknesses were observed in the response of some operating crews to emergency situations (Section 3.2). This matter should receive prompt attention by the staff, with appropriate involvement of NUMARC and/or the Institute of Nuclear Power Operations. The requisite organizational factors approaches needed to deal with emergency situations should be well understood at this stage of maturity of nuclear power plant operations. In addition to the lessons learned in response to actual emergency situations, the staff and licensees have had numerous opportunities to observe and learn from operating crew response during requalification examinations and emergency plan exercises. We recommend that the weaknesses observed be corrected on an expedited basis.

We are concerned by the two events in which engineered safety features (ESFs) were bypassed (Section 3.3.4). (Neither of these events was raised to the level warranting an AIT and, in one of these cases, the ESF was bypassed without the knowledge of the shift supervisor.) It is not clear from the study if these events were investigated appropriately by the Regional Offices. We believe that occurrences of this kind may represent a serious "safety culture" problem within the licensee organization. The staff should thoroughly review licensee corrective actions for events of this nature to ensure that the real root causes of the events have been dealt with in a manner that will prevent their recurrence. We do not believe that it is sufficient for the licensee to state in its licensee event report (LER) that the control room operator was reprimanded and provided with remedial training; the licensee needs to thoroughly evaluate and correct any "safety culture" issues raised by such events. However, we caution against the staff assuming the role of "de facto management" by prescribing, as opposed to reviewing, licensee management actions.

We are concerned by the statement in Section 3.5.1 that licensees had prepared an LER "in almost every case" but that "In some cases, it was difficult to tell that the reports (LERs) described the same event. It appears in these cases that the licensee failed to consider the human performance aspects of the event or failed to include that information in the report." During our meeting with the staff, we suggested that the draft study would be strengthened by including a discussion of the completeness of each associated LER with the evaluation of the individual events. We also suggested that a more detailed evaluation be made of this apparent weakness in the present LER program. AEOD chose not to follow our suggestions.

Summary and Conclusions

We believe that the AEOD study has been useful in focusing the attention of NRR and the Regional Offices, as well as that of the industry, on human and organizational performance issues. We agree with AEOD's plan to continue this activity (as described in Section 4.0 of the study) until these issues have been effectively addressed. As discussed above, we recommend that the Commission provide policy direction to AEOD on the matter of its charter, with respect to evaluating the performance of NRC staff organizations in the course of carrying out studies of this nature.

Sincerely, Paul Shewmon Chairman

References:

1. U. S. Nuclear Regulatory Commission, NUREG-1275, Volume 8, "Operating Experience Feedback Report - Human Performance in Operating Events," December 1992

2. SECY-92-407, dated December 9, 1992, for the Commissioners from James M. Taylor, Executive Director for Operations,

Subject:

The Independent Role of the Office for Analysis and Evaluation of Operational Data in the Assessment of Operational Experience and the Investigation of Operational Events