ML20036B834
| ML20036B834 | |
| Person / Time | |
|---|---|
| Site: | 05200002 |
| Issue date: | 05/21/1993 |
| From: | Stewart Magruder Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 9306030249 | |
| Download: ML20036B834 (34) | |
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May 21, 1993 Docket No.52-002 APPLICANT: ABB-Combustion Engineering, Inc. (ABB-CE)
PROJECT:
CE System 80+
SUBJECT:
PUBLIC MEETING APRIL 19 THROUGH 21, 1993, REGARDING DESIGN FEA-TURES REVIEW FOR THE CE SYSTEM 80+
From April 19 through 21, 1993, a public meeting was held 'at ABB-CE facilities in Windsor, Connecticut, between representatives o'. une U.S. Nuclear Regulatory Commission (NRC), ABB-CE and Brookhaven National Labor,atory '(BNL). provides a list of attendees.
The topics discussed during the meeting included design features review, draft safety evaluation (DSER) human system interface (HSI) open issues, Supplement 1 to NUREG-0737, " Clarification of TMI Action Plan Requirement" requirements for the Safety Parameter Display System, Task Analysis comments, Operating Experience Review open issues, and ABB-CE's Human Factors Engineering (HFE) Tracking of Open Issues System. A summary of each of the topics discussed is provided below and, where appropri-ate, agreements between the NRC and ABB-CE are indicated. A detailed discus-sion of these topics will be provided in the report on the design features review.
Desian Features Review The NRC staff and BNL personnel conducted an onsite review, from April 19-21, 1993, of the Nuplex 80+ control room mockup, located at facilities of ABB-CE in Windsor, Connecticut.
The onsite review addressed the following standard features of the Nuplex 80+ exemplified in the RCS panel: DPS Display Hierar-chy, DIAS Alarm Tile Display, DIAS Dedicated Parameter Display, DIAS Multiple Parameter Display, CCS Process Controller Display, and CCS Pushbutton Switch Configuration.
In addition, characteristics of the Integrated Process Status Overview (IPS0) were also reviewed in relation to tasks performed at the RCS panel.
The following activities were accomplished as part of the review:
o Discussion of ABB-CE's design process including how the findings of t
analyses such as the operating experience review, function analysis, task analysis are incorporated into the design.
o Demonstration of features and characteristics.
o Assessment of control and display availability of the RCS panel and IPS0 based on walkthroughs and talkthroughs of tasks from Emergency Procedure Guidelines and initiation and control of selected Critical Safety Function Success Paths.
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Assessment of the RCS panel and IPS0 using human factors engineering design guidelines.
During the entrance discussion, ABB-CE confirmed that the applicable documents that describe Nuplex 80+ design features are (1) those specified in its April 30, 1992 letter (ALWR-92-203, 1C-92-092), (2) Nuplex_80+ Advanced Control Complex Design Bases (NPX80-IC-DP-790-01, Attachment'l to ABB-CE letter dated September 23,1992, LD-92-102), and (3) Control Complex Informa-tion System Bases for Nuplex 80+ (NPX80-IC-DB791-01, Attachment 2 to ABB-CE letter dated January 18, 1993, LD-93-005).
The detailed results of the onsite evaluation will be provided in 'a report that is currently being prepared, including a desktop review of ABB-CE's de ign documentation.
In addition, the NRC staff and BNL met with ABB-CE on i
May 13 and 14, 1993, and discussed the results of the onsite evaluation and completed additional onsite followup.
D_SER HSI Open Issues The following DSER open issues were discussed during the onsite evaluation:
(1) shape and salience coding to prioritize alarms, (2) flash coding of alarms, (3) size coding of alarms, and (4) encoding methods used in the control room.
ABB-CE clarified its use of size coding of alarms and its relationship to color, shape, and flash rate.
The design specifications for alarm tile symbols indicate that symbols for new alarms are slightly larger than those for existing and cleared alarms.
However, alarm state is primarily coded by color and flash rate.
Operators are not expected to make discriminations between alarm tiles based on tile size. Therefore, this characteristic may_be
-disregarded for the purposes of this review. The issue regarding size coding is closed.
During the onsite evaluation, ABB-CE was requested to consider performing a small-scale demonstration / evaluation to provide. additional evidence that the alarm coding scheme as a whole, including shape, brightness and flash coding can be used effectively. The basis for this_ request is Criteria 6, Element 6 (HSI) of the NRC's HFE Program Review Model which states:
The selection and design of HSI hardware and software approaches-shall be based upon demon-strated criteria that support the achievement of human task performance requirements. Criteria can be based upon test results, demonstrated experi-ence, and trade studies of identified options.
This request is under consid-eration by ABB-CE.
The remaining issues are still under review by the NRC staff and what is required to~ bring closure will be provided in the design 1
features evaluation report.
Safety Parameter Display System (SPDS)
On the basis of the onsite evaluation of the Integrated Process Status Overview (IPS0), the NRC staff concluded that it was concise, rapid,
.(
. May 21, 1993 continous, and convenient, in conformance with the SPDS requirements of Supplement 1 to NUREG-0737. During the onsite meeting, the staff requested that ABB-CE provide a docketed submittal that would address the SPDS requirement for minimum information displayed.
Specifically, the submittal should provide ABB-CE's commitment with regard to the five safety functions and associated parameters detailed in Table 2 of NUREG-1342, "A Status Report.
Regarding Implementation of Safety Parameter Display Systems."
(After the meeting ABB-CE requested and the staff agreed that a commitment to add the NUREG-1342 specific parameters, as well as containment hydrogen concentration, by entering them into the ABB-CE Tracking System, would provide an acceptable resolution of this issue.) The detailed results of the onsite evaluation regarding SPDS, including the status of each Supplement 1 to NUREG-0737 requirement for SPDS, will be provided in the design features evaluation report.
Task Analysis The NRC staff is currently reviewing ABB-CE's task analysis submittal dated January 18, 1993.
Some comments (Enclosure 2) regarding ABB-CE's submittal were discussed during the onsite meeting. The staff and ABB-CE will complete its discussion of the task analysis submittal during the upcoming meeting on May 13 and 14, 1993 (Windsor, Connecticut).
Operatino Experience Review (OER) Open Issues lhe April 6, 1993, conference call minutes discusses OER open issues.
During the conference call, the NRC and ABB-CE established a path to resolution of the following open issue: ABB-CE is expected to respond to the " Operating Experience Issues Based upon Interviews with System 80 Operators" (BNL TER dated March 29,1993).
The NRC staff and ABB-CE agreed, as noted'in the April 6,1993, conference call minutes, to the following path to resolution of this issue: ABB-CE agreed to develop an initial response (and final response) to the above referenced operating experience issues by indicating those issues that are addressed in the System 80+ design versus those that should be tracked and resolved in its HFE Tracking System.
The NRC agreed that this OER issue is resolved by the above initial response to the operating experience issues. During the April 19 through 21, 1993 onsite meeting (Windsor,.
Connecticut), ABB-CE satisfied its commitment by providing the initial-response (Enclosure 3, Operator Interviews Findings Disposition).
As also agreed and noted in the April 6,1993, conference call minutes, ABB-CE's final response will indicate the design feature or document that resolves'those issues addressed by the System 80+ design.
i ABB-CE's HFE Trackino System The verification of proper implementation of the ABB-CE Tracking System, is discussed in the April 6,1993, conference call minutes.
The NRC staff and ABB-CE agreed that one means of resolving this issue would be an acceptable onsite implementation audit of the tracking system.
During the onsite evaluation, the staff evaluated the Tracking System.
For each issue the system is structured as follows:
issue number, originator, responsible
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- May 21, 1993 engineer, resolution commitment date, description of issue, resolution date, implementation (document number and revision, responsible section and implementation date), approval signature for resolution and implementation, and comments. Currently, there are 31 issues in the Tracking' System.
Although the Tracking System provides the noted information, it is not yet fully functional (e.g., a printout cannot be generated).
The NRC staff expects a computer dump of the entire file when it is available. The staff finds ABB-CE's approach to tracking of HFE open issues acceptable and considers this issue closed.
OII InM9thi D
Stewart L. Magruder, Project Manager Standardization Project Directorate.
Associate Directorate.for Advanced Reactors
.and License Renewal Office of Nuclear Reactor Regulation
Enclosures:
As stated cc w/ enclosures:
See next page DISTRIBUTION w/ enclosures:
Docket: File,
PDST R/F DCrutchfield PShea PDR MFranovich TWambach SMagruder TEssig RPerch, 8H7 Distribution w/o enclosures:
TMurley/FMiraglia,12G18 RBorchardt JMoore, 15B18 GWest, 10024 ACRS (11)
EJordan, 3701 GGrant, 17G21 GBagchi, 7H15
- see previous concurrence OFC:
LA:PDST:ADAR
'HHFB:DRCH PM:PDST:ADAR (A)SC:P
- ADAR NAME: PShea*
GWest*
SMagruder:sg*
TEssig DATE: 05/20/93 05/20/93 05/20/93 05/7\\/9 0FFICIAL RECORD COPY:
DOCUMENT NAME: MSUM0419.SLM
ABB-Combustion Engineering, Inc.
Docket No. 52-002-cc:
Mr. C. B. Brinkman, Acting Director Nuclear Systems Licensing ABB-Combustion Engineering, Inc.
1000 Prospect Hill Road Windsor, Connecticut 06095-0500 Mr. C. B. Brinkman, Manager Washington Nuclear Operations ABB-Combustion Engineering, Inc.
12300 Twinbrook Parkway, Suite 330 Rockville, Maryland 20852 Mr. Stan Ritterbusch Nuclear Systems Licensing ABB-Combustion Engineering, Inc.
1000 Prospect Hill Road Post Office Box 500 Windsor, Connecticut 06095-0500 Mr. Sterling Franks U. S. Department of Energy NE-42 Washington, D.C.
20585 Mr. Steve Goldberg Budget Examiner 725 17th Street, N.W.
Washington, D.C.
20503 Mr. Raymond Ng 1776 Eye Street, N.W.
Suite 300 Washington, D.C.
20006 Joseph R. Egan, Esquire Shaw, Pittman, Potts & Trowbridge 2300 N Street, N.W.
Washington, D.C.
20037-1128 Mr. Regis A. Matzie, Vice President Nuclear Systems Development ABB-Combustion Engineering, Inc.
1000 Prospect Hill Road Post Office Box 500 l
Windsor, Connecticut 06095-0500 i
v, MEETING ATTENDEES APRIL 19 THRU_21, 1993 NAME
_ORGANIZATIQN Garmon West, Jr.
NRR/DLPQ/LHFB-Daryl Harmon ABB-CE Robert Fuld ABB-CE-Bob Bryan ABB-CE Bob Rescarl ABB-CE Bill Stubler BNL Jim Higgins BNL i
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COMMENTS REGARDING TASK ANALYSIS SUBMITTAL DATED JANUARY 18,.1993 e '
1.
INTRODUCTION The NRC Human Factors Engineering Program Review Model (PRM) for advanced evolutionary reactors specified that a task analysis (Element 5) should be performed. ABB-CE described their task analysis in Section 18.5 of CESSAR and also in ' System 80+ Function and Task Analysis Final Report * (dated 1/89, docketed 4/8/92). The staff,in the Draft Safety Evaluation Report, identified deficiencies in the scope and depth of analyses provided by ABB CE. His was idendfied u Open Issue 18.7. In response to this open issue AllH.CE submitted their proposed task analysis revision for CESS AR, Section 18.5 (dated 1/18/93)(reference 2, below). This revision is currently in draft form. However, because it represents ABB CE's most current descri ption of task analysis including responses to issues identified in the DSER, the NRC has agreet to review this draft document.
2.
OBJECTIVES ne objecti' :s of this review were to (1) evaluate the scope of the analyses proposed by /.BB-CE, (2) evaluate ABB-CE's task analysis methodology, and (3) to evaluate the results of a task analysis which was conducted and analy7ed by ABB-CE to provide design input for the Reactor Coolant System panel of the Naplex 80+ control room. De third objective was not accomplished, however, since the review of the scope and methodology raised questions that had to be addressed before the review of the RCS analysis could be completed. Evaluation of DSER issucs resoludon was addressed within each objective.
- 3. METHODOLOGY 3.1 Material Reviewed The following ABB-CE documents were used as the basis for the review:
Proposed CESS AR Section 18.5 on functional task analysis (proposed as an amendment to CESSAR),1/18/93
" System 80+ Function and Task Analysis Final Report," 1/89 Human Factors Program Plan for the System 80+ Standard Plant Design (NPX80 IC-DP790-01, Rev 01),12/15/92 LD 92-065: Letter from C. B. Brinkman (ABB CE) to NRC," System 80+
Supplements to R AI Responses," 5/8/92
+ LD 92-102: Letter from C. B. Brinkman (ABB-CE) to NRC," System 80+ Human Factors Documentation Submittal." including Attachment 2 "Nuplex 80+ Compliance with NUREG-0737 Supplement 1 Requirements," 9/23/92
Draft Safety Evaluation Report issues," 1/18/93 1
+
3.2 Review Procedure ne following is a brief chronology of activitics that occurred during this review:
- 1. A preliminary review was conducted of the ABB CE document," System 80+ Function and Task Analysis Final Report" (dated 1/89, docketed 4/8/92) during PRM Elements 3 and 4. Final n: view of this document was defermd from PRM Elements 3 and 4 until element 5.
The following materials were consulted as part of the evaluation:
NRC HFE Program Review Model for Evolutionary Reactors (PRM),7/92
. NUREG-1492 Draft Safety Evaluation Report (DSER),9/92
- 1etter from T. V Wambach (NRC) to ABB CE,"Public Meeting September 10 and 11 Regarding Human Factors Engineering (HFE) Design issues,"(docket No. 52 002),10/92 Card. S. K., Moran, T. P. and Newcll, A. (1983) The psychology of human. computer interaction, New Jersey: Lawrence Erlbaum Associates, pp,23-97
' Rasmussen, L (l986). Information processing and human-machine interaction: An approach to cognitive engineering, New York: Elsevier Science (North-Holland) 4.
Evaluation of Element 5 - Task Analysis The foljowing review is organized in three major subsections. The Grst subsection reviews the scope of the task analysis effort proposed by ABB CE. The second subsection reviews the methodology proposed by ABB-CE. The third subsection addresses task analysis related issucs deferred from the Element 4 review.
4.1 Task Analysis Scope The purpose of this section is to compare the scope of the task analysis that ABB-CE has committed to perform to the scope speciGed by PRM Element 5 - Task Analysis and the scope related items identified in the September 10th and lith meeting between NRC and ABB CE. Tobic 1 summarizes the task analysis scope identiGed by these two documents.
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4.1.1 DSER Issues In the September 10th and 1Ith meeting, the staff requested that ABB-CE incorporate the task analysis methodology into Section 18.5 - Functional Task Analysis of CESSAR-DC with specific modincations. The full list of modifications n: quested by the NRC is shown in Appendix A.
His section addresses DSER issues related to the scope of the task analysis. In some cases DSER items are closely related to specific PRM criteria. In these cases the relevant PRM criteria are referenced and discussions arc deferred to the PRM section.
Draft TRfor Ekment 3 Task Analysis page 2 l
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Table 1. Task Analysis Scope PRN Criterion 1: De scope of the task analysis shallinclude all operatiora, maintenance, test and i m analym shall he directed to the full range of plant operating modes, including start tip, normal opera abnormal tveradons, transient corxlitiora, low power and shutdown conditions. De analyses sball include ta performed in the contro1 room as well as outdde of the control ronm.
Tbc following were identified as scope items in the September 10th and lith Mcedng:
Item A: Full range of operating modes including low power and abnormal operations.
tsem C Identify through thunan Reliability Analysis criGeal tatkA which impact Kafety and complete a task analysis for any such tasks.
lism E: Task analysis for plant operation witboot (be DrS.
Isam G: Task anafyses for:
-Interacdons between and tunong the crew in the control room
. Interactions betwcen the crew in the control room and other personnel in the plant Equipment, documenuttion, arxl. supplies required to sup ort personnel during normal, abnormal, and emergency operadons
-Information needed for compicung tatka or for reconstructing an event that may not be explicidy identified in the generic process
- Maintenance, inspecdon, and test acdvitics that take place in the control room item H: Task analyses for 1.,3, and & person operudng crews litm I; Analyses for-Maintenance work order tracking and tagout
. Tracking status of equipenent under test, surveillance, or repair
-Impact of tracking system / scheme on normal, abonnnat and emergency operations hema Cdterion-Fu11 range of operating rnodes include low power and abnormal operations events provide justincation for not including an cycnt on low power operations during the task analysis for the RCS panel Evahairion: Sec review of PRM Criterion 1.
i ltern_B Cdreriore Document the resolution of the recommendations for reallocation of function noted on the following pages in Appendix I of the System 80+ Function and Task Analysis Final Report (dockeled on May 8,1992): pp.1-45.1-5,1-7 through I-12, DrAp TRfor Element 3 Tast Analysis Page3
a Evaluation: The reviewers have not received matcrial addressing this criterion. ABB-CE is requested to provide inforrnatinn regarding resolution of this item.
It-m E Cruerion:
Provide justification for not completing a task analysis for operation without the DPS.
Evaluation: Secdon 18.5.1.5.1 of Reference 2 lists 15 event sequences that will be addressed by the task analysis. Event M - Design Basis Failures of DPS and DIAS indicated that this issue will be addreued by the task analysis. This item is acceptably addressed.
hems E Criterion: F Provide posidon descriptions for people expected to be in the control room during normal, abnorma], and cmergency operauons.
Evaluation: An acceptable description of position descriptions is provided in LD-92-065.
hCHLG and H Criterion G : Providejustification for not completing a task analysis for the following:
interactions between and among the crew in the control room interactions hetwecn the crew in the control room and other personnel in the plant Criterion H:
Discuss ABB-CE's position regarding the performance of task analyses for 1,3, and 6-person operating crews.
Evaluation: A response from ABB-CE regarding items G and H is provided in LD-93-005. In thisletter ABB-CE states:
Posidon descriptions for connot room personnet have no irnpact on the task analy$is and are not provided as pan of the task analysis. Position or job descriptions are primanly an operations and training requin:ments concern (" Job Analysis") for a COI. appticant. It is assumed that the contml rcom Dir$ TRfor Element 3 Task Analysis Page 4
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F complement meets NRC r.taffing requirements and individuals are NRC qualified. Furmer refinement in the form of positiun descriptions is not needed for task analysis or HS! design purposes.
ABB-CE's response is directed towards qualineations and not that use of the control room by muldple crew members. In ABB-CE's human factors program plan, Section 2.3.1 generally indicates that staf6ng and configuration analyses have been performed. !!ow were these evaluations performed if not through task analyscs. ABB CE has not provided analyses to indicate that the control room supports the coordinated activitics of crew members dunng scenarios when multiple cmw members will be in the control room.
PRM Elements 4 and 5 require that control room crew staffing issues be addressed. PRM Element 5 Criterion 3 requires that detailed task descriptions address staffing and communication requirements including the number of personnel, their technical specialty, and specific skills. PRM Elcment 4 Criterion 2 states that the allocation of functions shall be made to reflect the number and level of skills of personnel required to operate and maintain the system. PRM Element 4, Criterion 2 was not addressed by ABD-CE during the PRM Element 4 review and was defem:d to Element 5 (see Section 4.2.3 of this technical niport).
ABB-CE is requested to indicate how they will address control room activides with varying levels of staff. These analyses should be used to verify minimum control room staffing assumptions.
These analyscs should addre.u requirements for communicating information and coordinating control and monitoring actions between control room personnel. For example, transitions between control panels should be analyzed using link analysis or similar techniques to evaluate workload, t
ite m G Criterion:
Provide justification for not completing a task analysis for the following:
equipment, documentation, and supplies n: quired to support personne! during normal, abnormal, and emergency operations information needed for completing tasks or for reconstmeting an event that may not be explicitly identified in the gencric procedures task analyscs for maintenance. inspection. and test activitics that take place in the control room input to personnel training programs Evaluation: The documentation provided by ABB-CE did not address this criterion. ABB CE is requested to indicate how these issues will be addressed.
ItemI Criterion:
Provide commitment to addre.u the following issues:
maintenance work order tracking and tag out scheme for control room instruments and equipment identified via CRT and Oat panel displays an account of how operators will track the status of equipment under test, survcillance, or repair Drqp TRfor Element $ Tast Analysis Page$
impact of tracking scheme / system on normal, abnormal, and cmergency operations ABB-CE provided a description of the maintenance work order tracking and tagout Evaluation:
process in LD 93 005. In this letter ABB CE states that ma tagout system will not be required by the operators in the controlling workspace but by othe i
personnel in the rnain control room. The letter does not resolve the apparent contradicd the statement that maintenance work order tracking and tagout are performed outside of the cont room and the statement that data input is performed inside the control room. ADB CE should clarify by whom and where both the inputs and outputs of the maintenance work order trackin and tagout will be handled.
%e letter does not describe how operators will track the status of equipment under test, surveillance, or repair. Instead,it states that these tasks will be controlled by COL appi: cant administrative procedures.
The letter also states that maintenance work order tracking and tagout will have no impact on the HS1 control room design. However, operators must be aware of the status of both maintenance work orders and tagouts. Dus consideration should be given to the pre >entation of this infonnation to the operators. Aho, the success path monitoring algorithms of the Data Processing System may produce safety and non-safety alarms when plant components become unavailable.
Rese alarms will affect operator activities. Then:forc, work order tracking and tagout should be addressed. ABB-CE is requested to provide a commitment to address these issues in detail via task analysis or other means.
4.1.2 PRM Criteria EfBLCnterien_1 Subcriterion lo: De scope of the task analysis shall include all operations, maintenance, test and in~spccdon tasks.
Evoluotion: CESS AR Section 18.5.1.5.1 lists 15 cvent sequences for the Functional Task Analysis. ABB CE pmposes these as a representative cross section of operadons for the Nuplex 80+ control room. This list emphasizes plant operadons including technical specification surveillances. In does not address the generation of maintenance work orders, tagout of plant equipment, or the test and inspection of liSI components in the control room. nc generation of mamtenance work orders and tagout of plant equipment are addressed by DSER Item lin Section 4.1.2 of this review document. The test and inspection of HSI components in the control room requires consideradon of the HSI design.
ABB-CE is requested to describe in more detail how their analyses will address the generation of maintenance work orders and tagout of plant equipment. In addition ABB-CE is requested to describe how its human factors evaluation program will addrun those tasks associated with the test and inspec on of HSI components in the control room.
Subcriterion 1h De analyscs shall be directed to the full range di plant operating modes, ixludin3. tart-up, normal operations, abnormal operations, transient condidons, low powcr and shutdown conditions.
DrQ TRfor Elemem 5 Task Analyns pay 6
Evaluation: CESSAR Secdon 18.5.1.5.1 (pp.18.5 8 to 18.5-9) lists 15 event sequences for the 9
scope of the Functional Task Analysis. ABB CE proposes these as a represent.uive cross-sectinn of operations for the Nuplex 80+ control room. However, normal and abnormal operations and technical speci0 cation survcillance tasks an: not explicitly defined. Normal operations are apparently addressed by the ' steady state" portion of Event A - Startup with Steady State and Transient Power Operations. Low power conditions are apparently addressed by Event A - Startup with Steady State and Transient Power Operations and Event B - Shutdown with Shuidown Decay Heat Removal.
Abnormal conditions art addressed by Event N Selected Abnormal Operation Procedures, but specific abnormal events are not deOned. Surveillance tasks are apparently addressed by Event 0 -
Selected Tech. Spec. Surveillances. However, specine surveillance tasks are not listed.
ABB CE is requested to clearly dc0nc events for normal operations and low power operations (e.g., Low Powcr Operations: X to Y'7o Power). ABB-CE is also requested to describe the speciEc cvents that will be addressed by the categorics: abnormal plant operations and technical speciGcation surveillance tasks.
Subcriterion Ic The analyscs shall include tasks performed in the control room as well as outside of the control room.
Evaluation: CESSAR Section 18.5.1.5.1 (pp.18.5 8 to 18.5-9) lists 15 event seguences for the Functional Task Analysis. ABB CE proposes these as a representative cross-section of operatiorts for the Nuplex 80+ control room. This list does not appear to address tasks performed outside of the control room. such as local contml stations. However, task analyses oflocal control panel annunciator, display and control inventory are explicitly stated in Table 1.18.3 1 in Section 1.18.3 of ITAAC and the Human Factors Program Plan mdicates that task analyscs will be performed for LCSs necded to perform EOPs.
EILhtCriteriend. -
Criterlon: The ta.sk analysis results shall provide input to the personnel training programs.
r Evaluation: A commitment to provide vendor task analysis n sults to the licensee is provided in ABB CE's Human Factors Program Plan (sce pages 49 and A30 of the Plan). 'This criterion is acceptably addressed.
4.2 Task Analysis Methodology This secdon reviews the technical basis and typical outputs of the functional task analysis submitted by ABB CE and enmparcs them to the requirements of PRM Element 5.
4.2.1 General Comments Section 4.2 of Reference 1 states that the functional task analysis was hav.d in part on the human processor model for simpic decision processes (Card et al.,1983). The following comments address the application of this model by ABB CE to the functional task analysis methodology.
Drap TRfor Element 3 Ta.<L Analysis pap 7
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- 1. De ABB CE Human Factors Program Plan indicated that " future FTA acdvities will modify the amount of sorts performed and the level of documentation archived" (
Plan indicates that the " basic FTA methodology will remain unchanged," p. 52). Even tho clarification of the meaning of the above statement is required befom the methodology can be fully reviewed.
- 2. The task analysis provided addressed a control room panel and a general methodology was inferred from the example, it is unclear how the methodology would change for the evaluation of other tasks, panel, or local control stations, e.g., what additional factors may be considered in the analysis.
- 3. The Model Human Processor (Card et al.) represents the integration of psychological theodes and principles for modelling simple dect. ' in processes. It consists of three interacting subsystems:
(1) the perceptual system, (2) the motor spun, and (3) the cognitive system. ABB-CE uses portions of this model to develop time estimates for individual task elements. This is an acceptable model for evaluating simpic decisions and manipulations of a human-system interface. However, it does not model knowledge-based behavior (Rasmussen 1986) associated with diagnosis of plant conditions and plann',g/sclection of responses for plant failures. ABB-CE is requested to provide u
a description of how knowledge-based behavior such as plant diagnosis will be addressed in its functional task analysis, or a justification for not including know!cdge based behavior in the task analysis. Dejustification should include a discussion of when and how knowledge ba.ed behavior will be addressed elsewhere.
- 4. The Mode! Iluman Processor uses three estimates of human performance (1) Slowman (worst performance),(2) Middleman (nominal performancc), and (3) Fastman (best performance). De discussion provided by Card et al. (pp. M - 45) indicates that both the Middleman value and the range (Fastman-Slowman) should bc considered when describing human behavior. The criterion used by ABB-CE for evaluating task performance time conflicts is based only on the Middleman value. His may result in a failure to flag findicate) ta3ks that cannot he perfmmed by operators who have reaction times that approach the Slowman value. In the reviewers' opinion,it is more appropriate to analy7e tasks using values that would accommodate a greater percentage of the distribution (e.g., the Slowman value). ADD-CE is requested to describe and clarify die acceptability and limitations of using the Middicman value as a criterion for initial screening of the acceptability of tasks. ABB CE is also requested to provide independent veri 6 cation through time studies or other means that the~ operator nuponse times calculated using the Model Human Processor adequately renect human performance.
- 5. De analyses of operator response times that wen: perfonned using the Model Human Processor make no provisions for operator errors such as slips (e.g., accidental activation of the wrong button) which may result in higher n:sponse times. ABB-CE is requested to describe the sensitivity of the task loading analysis criteria to operator errors.
- 6. CESSAR Tahicl8.5.1-2 and Table 4.3 3 of the System 80+ Function and Task Analysis Final Report provide values for minimum access dme required for CRT displays for three different t.onditions. "Ihe derivation of these values from dic equations shown on thcsc tables is not cicar, t.
ABB CE is requested to clarify these calculations.
7, in CESS AR Table 18.5.1-3 equations are provided for reaction time for three conditions:
i physical matches, name matches, and class matches. ABB-CE is requested to explicitly state the values used for S, Se, and Sm and references for these specific values.
p 0 rap 1Rfor Etcinent 3 Tad Analysis PageR J
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4 4.2.2 DSER Issues In the September Rhn and 1Ith meeting. the staff requested that ABB CE incorporate the task analysis methodology into Secdon 18.5 - Functional Task Analysis of CESSAR DC with specific modifications. He fulllist of modifications requested by the NRC is shown in Appendix A. His section addmsses DSER issues related to the task analysts methodology. In some cases, DSER items am closely related to specific PRM criteria. In these cases, the relevant PRM critcda are referenced and discussions are deferred to the PRM section.
Item C Criscrion-Commit to identify through Human Reliability Analysis for System 80+, critical tasks which impact safety, and to complete a task analysis for any such tasks that are identified.
Evaluation:
See PRM Criterion 2 Ite m D Criterion-Address details of Critcrion 3 in the NRC's HFE Program Review Model.
Evaluation:
See PRM Criterion 3 4.2.3 PRM Criteria PRM Critmica.2 Criterion: The analysis shall link the identified and described taks in operational sequence.
diagrams. A review of the descriptions and operational sequence diagrams shallidentify which tasks can be considered "cridcal in terms of importance for function achievement, potential for human error, and impact of task failure. Human actions which are found to affect plant risk in PRA sensitivity analyses shall also be considered " critical." Where critical functions are automated, the analyscs shall consider all human tasks including monitonng of an automated safety system and back-up actions ifit fails.
Evaluation: De functional task analysis methodology pn:sents tasks in timeline diagrams similar to operational sequence diagrams dexdbed in the criterion above. This mpresentation satisfies the Plud requirement for operauonal sequence diagrams.
De functional task analysis methodology identifies tasks for which the time required for execution i
may be in conflict with the time available for execution. However, the functional task analysis methodology does not specifically identify tasks that can be considered "cdtical" in terms of function achievement, potendal for human error, and impact of task failure as described in the criterion above.
ABB-CE has recently completed a PRA sensitivity analysis to identify human actions that may be found to affect plant risk. As a result of this analysis,10 critical operator tasks were identified.
DSER licm C states that these crideal tasks should be fur 6er evaluated using task analysis. ABB-CE is requested to describe these 10 cdtical tasks in its task analysis submittal and provide a commitment to perform task analyscs for these 10 tasks.
Draft IRfor Eternent 3 Tast Analysis Page 9
O PRM Criterion 3 Criterion: Tasks analysis shall begin on a gross level and involve the development of detailed narradve descriptions of what personnel must do. Task analyses shall define the nature of the input, process, and output required by and or personnel. This criterion is composed of nine subcriteria (a to i). The mview of each is discussed below.
Evalunrion: *Ihc functional task analysis provides a valuable analysis of infonnation reguirements at the gross level. However, additional information is required for the following subcnteria: a, b, c, e, f, g, and h.
Subcriterion 3at Information Requimments Information requimd, including cues for task initiation Information available Evaluarion: The funedonal task analysis describes a methodology for identifying information requirements for 15 selected events (CESSAR Section 18.5.1.5.1). Information requirements are -
derived for individual steps of these events. The descripdon of the individual stcps of these events are based on " Combustion Engineering Emergency Procedure Guidelines" (1987). Time lines for -
these events are based on process dme estimates derived by "cvaluating data from specific event profiles. based on operator expericnce and process transient rc.sponse models" (Section 18.5.1.5.3; of Reference 2). Information requirements derived from this analysis are summaried for the RCS panelin System 80+ Function and Tasks Analysis Final Report. This aspect of the analysis is acceptable.
t Subcriterion 3b Decision-Making Requimments Description of the decisions to be made (reladvc. absolute, probabilistic)
Evaluadons to be performed Decisions that are probable based on the evaluation (opponunities for cognitive errors, such -
as capture errors, will be identified and carefully analyzed)
Evaluation: The functional tasks analysis models all operator decisions as simple, rule based behavior. More complex decision-rnaking such as diagnosis of plant condition during complex events (e.g.,inuidple failures)is not addressed. Opponunities and consequences for human errors am not addressed for either errors of intent or errors of execution. For example, cognitive errors such as misdiagnosis of plant condition are not addressed. Neither are performance errors such as improper activadon of a control (e.g., wrong control, wrong action). ABB{E is requested to dev: ribe how knowledge-based behavior and operator errors will he addressed.
Subcriterion 3c: Response Requirements Action to be taken Overlap of task requirements (serial versus parallel task elements)
Frequency Speedrimeline requirements Tolcancelaccuracy
~
Operational limits of personnel performance Operationallimits of machine and software Body movements requimd by action taken Drgp 1Rfor Elrment.T Tast Analysis
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Evaluation: De applicability of the functional task analysis to the specific Resportse Requirements of subcriterion 3c are described below:
3c 1. The funedonal task analysis methodology addresses the following Response Requirements:
- Actions to be taken
- Frequency Spccd/ time line requirements
- Tc!emnce/accumcy
- Operational limits of personnel performance (comparison of the time available to perform actions to the time theoretically required to perform these actions).
The above categories of response requirements are addressed by ABB-CE's funetional task analysis methodology. The reviewers have questions regarding the ways in which the values for these response requirements are calculated using the Model Human Processor. These concerns are expressed in Secuon 4.2.1 Ocncral Comments.
3c-2. The functional tack analysic does not address ov-rlap of task elements. Section 18.5.1.1 of Reference 2 states: "The FTA will consider task clements to be additive and serially processed, unicss otherwise noted." No general consideradon is given to complex interactions of steps or personnel in the ETA.
3c-3. The operational limits of machine and software, such as cornputer response time. are not addressed by the ABB-CE task analysis.
3c-4. The body movements required for operation of the HSI are not adequately addressed; the task analysis does not consider the physical design of the control panels. Only very simple assumptions regarding target sie and hand movement distance are made. It does not take into account the effect of the position and frequency of required modons upon operator performance and fatigue.
'The func00nal task analysis addressed many of the issues described in this criterion. However, clarification is needed regarding the issues described in 3c.2,3c-3 and 3c-4 atxave.
Subtriterion 3d: Feedback Requirements
~
Feedback required to indicate adequacy of actions taken Evaluation: The issues of feedback is generally acceptably addressed for the tasks and HSI components addressed by this task analysis.
Subcriterion 3e: Work)oad j
Cognitive Physical Estimation of difficulty level Evaluation: Cognitive and physical workload are only addressed in terms of theoretical choice response thnes and physicaJ movement times. The analysis does not address concurrent tasks.
Drqft T)tfur Element 3 Tust Analysis Pop JI
multi. person tasks, or complex decision-making. ABB-CE is requested to descdbe these factors will be addressed.
Subcriterion 3f: Support Requirements Special/protecdve clothing Job nids or reference materials required Tools and equipment required Computer processing support aids Evaluorion: PRM Element 5 - Task analysis should address the use and accessibility of support requirements that are relevant to the operator's tasks. For example. job aids and reference materials (esgially procedurts) are important task support requirements for tasks addressed by ABB-CE's tasi analyses for the RCS panel. He task analyses should include issues such as coordination of procedure use among control room personnel, procedure lay-down space, and confliednp illuminadon requirements for paper documents and computer-bar.ed displays. ABB CE is requested to describe the degree to which support itquirements will be addressed by the task analyses.
Subcriterion:3g: Workplacc Factors Workspace envelope required by action taken Workspace conditions Locadon and condition of the work Environment Evaluation: PRM Element 5 -Task Analysis should address workplace factors. For exampic, the workspace envelope is one workplace factor important to ABB CE's task analyses for the RCS panel. (The other three workplace factors listed above are more relevant to tasks performed outside of the control room such as local control stations.) The task analysis should address the envelope of operator movements that result from required actions and the placement of controls and displays on the control panels. 'This analysis should address the frequency and distance of required movements. It should be conduc'.ed at two levels (1) movements within each control panel and (2) movements between control pancis. This analysis should take into account control room staffing levels. ABB-CE is requested to describe the degree to which workplace factors will be addressed in the task analysis.
Subcriterion 3h: Staffing and Communication Requirements Numher of persunnel, their technical specialty, and specific skills Communications required including type Personnel interaction when more than one person is involved Evaluation: In CESSAR Section 18.5.1.1,it is stated that the functional task analysis assumes task elements to be addidvc and serially processed. No general consideration is given to compicx interactions of steps or personnel in the FTA. These nu.umptions are in conflict with PRM criteria that address multiple crew members. ABB-CE is requested to des'cribe how such issues will be addressed.
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I
' fpr le, ays.>
10:2Wt1 FRCr1 Bl WPA Group TO tEC tRR (JF/N P.16
~
Subcriterion 31: Hazard Identification Identification of Hazards involved Evaluation: ne funedonal task analysis provided by ABB CE does not address tasks perfonned outside of the control room. Given that the curn:nt scope is for tasks performed in the main control room the identification of hazards is not relevant to the task analysis. ABB-CE is requested to describe whether it intends to addren haards in iu task analysis for other tasks.
PRM Criterion 4.
Celterion: ne task analysis shall be iterative and become progressively more detailed over the design cycle, ne task analysis shall be detailed enough to identify information and control requirements to enahic specificadon of detailed itquirements for alarms, displays, data processing, and controls for human task accomplishment.
Evaluation: %c funedonal task analysis identifies operator information requirements for displays and controls. ABB-CE is requested to describe how it will addn'ss the factors described above.
4.3 PRM Criteria-Based Evaluation from Element 4 The following is a review of PRM criteria from Element 4 that were deferred until Element 5 -Task Analysis.
ERMEement 4: criteria 2. 3. & 5.
Criterion 2: Unchanged functions that have modified function allocations shall be analyzed in s
terms of resulting human performance requirements based on the expected user population. This analysis should reficct (1) sensitivity, precision, time, and safety requirements. (2) required reliability, and (3) the number and level of skills of personnel required to operate and maintain the system.
Criterion 3: Modified functions (identified in Element 3) shall also be analy7ed in terms of resulting human performance requimments based on the expected user population. This analysis should ruficct (1) sensitivity, precision, time, and safety requirements, (2) required irliability, and (3) the number and level of skills of personnel required to operate and maintain the system.
Criterion 5: De results of analyses and trade-off studies shall support the adequate conGgurations of personnel and system-performed functions. Analyses shall confirm that the personnel clement can properly perfonn tasks allocated to them while maintaining operator situation awareness, workload, and vigilance. Proposed function assignment shall take the maximum advantage of the capabilities of human and machine without imposing unfavorabic requirements on cither.
Evaluarlon: Le functional task analysis methodology addresses considerations such as sensitivity and piteision. However, the number of personnel and level of skills of personnel are not addressed. Control room stafGng and skill levels were also addressed by DSER Items F, G, and
!! and PRM Element 5 Criteria 3h. ABB.CE in requested to indicate how the these issues will be addressed, l
Drqft 1Rfor Element 5 Task Analysis l'U$' II i
q s
J
5 Conclusions The review of the ABB.CE FTA indicated that the methodology adequately identifies control and display requirements. However, several issues were noted which n: quire further clarification before the methodology can be completely reviewed. In addition, the ABB-CE should clarify:
Whether the methodology described in at its full level of detail or whether it will condnue to be made more detailed through future iterations; Whether the methodology will be modified as it is applied to other tasks and panels in the control room; and Ilow the methodology will be modified to addren local control stations, e.g.. what factors will be analyzed beyond the analyses directed to the main control room.
6' 1
s Drgy TRfor Element 3 Tast Analysts page ]4
F Apr 16 1993 10: me s Fku1 ut n-PA treup vtfRAnwrgym pr;gy Appendix A Modifications to Section 18.5 - Functional Task Analysis of CESSAR.DC Requested by the NRC at the September 10th and lith Meeting e
Draft TRfor Eternent 3 Tast Analy. sis
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W W "
- M cup M
if.3]i)
In the September loth and lith meeting, the staff requested that ABB-CE incorporate the task analysis methodology into Section 18.5 - Functional Task Analysis of CESSAR-DC with the modtficadons listed below.
(A)
Full range of operating modes include low power and abnormal operations events provide justification for not including an event on low-power operations during the task analysis for the RCS panci (B)
Document the msolution of the recommendations for reallocation of function noted on the following pagen in Appendix I of the System 80+ Function and Task Analysis Final Report (docketed on May 8,1992); pp.1-45,I-5,I-7 through I-12.
(C)
Commit to identify through Human Reliability Analysis for System 80+, critical tasks shich impact safety. and to complete a task analysis for any such tasks that are identined (D)
Address the details of Criteria 3 in the NRC's HFE Program Review Model.
(E)
Provide justincation for not completing a task analysis for operation without the DPS.
(F)
Provide position descriptions for people expected to be in the control room during normal, abnormal, and emergency operations.
7 (G)
Provide justification for not completing a task analysis for the following:
interactions between and among the crew in the control room interactions between the crew in the control room and other personnel in the plant equipment, documentation, and supplies required to support personnel during nonnal, abnormal, and cmcrgency operations information needed for completing tasks or for reconstructing an event that may not be explicitly identined in the gencric process task analyses for maintenance, inspection, and test activitics that take place in the control room i
input to personnel training programs (Provide justiGcation for not providing results of the task analysis as input to the personnel training i
programs)
(H)
Discuss ABB-CE's position regarding the perfonfiance of task analyses for 1,3,
and 6-person operating crews.
Drqlt TRfor Element S Tast Analysis Page16
Apr %,1993 10:31Cri FR10M DL WPA troup TO tRC tRR (JF/N P.20 Provide commitment to address the following issues:
(I) maintenance work order tracking and tagotit scheme for control room instruments and equipment identified via CRT and flat panel displays an account of how operators will track the status of equipment under test, surveillance,or repair impact of tracking schemc/ system on normal, abnormal, and emergency operations Lastly, ABB CE committed to submit a document that addn:sses how Nuplex 80+
tie safety parameter display system requirements of Supplement I to NUREG-0737 September 30,1992 s
pag,;7 Dray TRfor Eternent 5 Task Analysis TOTAL P.20
4 OPERATOR INTERVIEW FINDINGS DISPOSITION LEGEND D
Indicates that the issue is either:
a) addressed by the System 80+ plant design, b) addressed by the Nuplex 80+ advanced control complex design.
c) adressed by existing Nuplex 80+ design documentation or guidance to assure the issue is addressed during implementation.
T Indicates that the issue has been entered into the human factors tracking system.
COL Issue for COL applicant - not a design certification issue.
4
1.
BACKGROUND l
The NRC Human Factors Engineering Program Review Model (PRM) was developed to support design cenincation reviews of advanced reactors under 10 CFR Pan 52. An Operating Experience Review (OER) was denned in the PRM as one of eight fundamental elements of a human factors engineering (HFE) program. An OER contributes, along with other HFE program elements, to the successful integration of plant personnel and systems, thereby supponing public health and safety.
The main purpose of the OER is to identify potential safety related issues which are followed to disposition by an issues tracking system. De OER provides information regarding the performance of fully-integrated predecessor systems (in an analogous way to full-mission validation tests which provide information about the achievement of safety goals and safety concems for the integrated system under review). The lessons leamed and msolution of OER issues may impact function allocation (changes in automation), system design, HSI design, procedures, training, etc.
Among the data requirements identified in the PRM are interviews with operators of predecessor plants in order to identify operating experience issues that can be assessed in the new design. This is especially significant in the case of an evolutionary design. ABB-CE has stated that:
The System 80+ design philosophy for both the plant and the control complex is evolutionary. Implicit in any evolutionary framework is the success of preceding generations: evolution is a process of modifying generally successful designs into improved ones. Conservative evolutionary design therefore emphasizes the solution of known problems, and the incorporation of established improvements.
(Fuld,1992, p.7)
However, the review of the ABB-CE operating experience n view for the System 80+ revealed that interviews with currently licensed operators of System 80 plants (predecessor to System 80+) were not conducted by the designers (Higgins & O'Hara,1993). Thus a gap in the OER was identified. -
2.
OBJECTIVE The objective of this effort was to conduct interviews with currently licensed operators of System 80 plants to support the identification and review of operating experience issues. Several factors should be considered when examining the results of these interviews:
The main goal was to identify issues for consideration in System 80+ design and review. However, the time available to accomplish the task was limited, so detailed i
explanations of all issues were not obtained. (More detailed evaluations of selected issues should be accomplished following a screening process - see the next item).
No effon to screen issues for applicability to the System 80+ design was made at this time. Therefore, some of the issues raised by operators may have already been.
addressed in the System 80+ design.
Operators raised issues associated with the secondary side and other non-safety aspects of the plant. While these are not of prime concern to the NRC safety review, they were included in this mpon for the benent of the designers.
~
As'per the PRM, information was sought related to (1) human performance issues, problems and sources of human error; and (2) design elements which support and enhance human performance.
Specific topicsincluded:
System 80 Operator Iraerviews Page1 I
- Function Allocation and Task Design Issues
- AlarmsIssues
- Indication and Display Issues
- Control Device Issues
- Ccmputers
- CommunicationIssues
- ProcedumsIssues
- Control Room Layout and Habitability
- Local Control Stations
- 3. METHOD 3.1 Review Team The review team consisted of two human factors specialists and one formerly licensed senior reactor operator (SRO) from BNL and the NRC.
3.2 Operators Interviewed Fourteen (14) licensed operators and control room supervisors panicipated in the interview. Their average years holding an operator's or a senior operator's license was 4.6 years (a = 2.2 years) and average time at their plant was 8.7 years (a = 1.4 years). The operators came from three different CE System 80 units.
3.3 Errgaration In preparation for the interviews, the review team performed a limited overview look at the Licensec Event Report (LER) related Sequence Coding and Search Scheme (SCSS) abstracts for System 80 operator event experience. Each SCSS abstract is part of a summary analysis of a particular LER called an "LER SCSS DATA" record. Also myiewed was several various sons of the LER database for System 80 units. This cursory review was conducted to familiarize the team with potential areas ofinterest.
Based on a search made several weeks prior to the interview date, there were 444 LERs related to System 80 units (during their roughly 22 plant-years of cumulative history oflicensed operations and shutdown) for which SCSS summary records were available. From the LERs, a total of 649 human actions (called " steps") had been categorized by personnel field and subdivision. Table 1 below provides a high level breakdown of selected fields and subdivisions pertinent to HFE.
I hii$A ss l
i Sptem 80 Operator interviews Page 2 i
a
- l Table 1. Summary of LER Human Action Categories 1
i PERSONNEL NUMBER PERCENT i
FIELD SUBDIVISION OF ACTIONS OF TOTAL
. j TYPE licensed operator personnel -
178 27.4 i
non licensed operator personnel -
30-4.6 '
q unknown utility personnel
-287 44.2 -
j unknown personnel and 54.-
8.4
-}
other/ utility personnel ACTIVITY test / calibration activity 192-
-29.6 operation activity 152 23.4 maintenance / repair activity 81 12.5-CAUSE intrinsic human error 378 58.2 task description inadequacy 168 25.9 inadequate man-machine interface 13 2.0 t
EFFECT commission of undesired task.
319 49.2 z
task analysis, or step
' i omission within alloued time 156 24.0 omission of task. analysis, or step -
115 17.7 3.4 Interview Procedure Upon arrival at the site, the team toured the control room training simulator to become familiar with
- t the human-system interface (HSI) and to observe potential topics for discussion (such as modifications made to the control room).
~
The interviews were conducted in February 1993. Operators wem interviewed as shift crews in '
groups of one to three by the three-member review team. A total of six groups were interviewed.
Each intersiew lasted approximately 1.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br />. For many of the interviews other individuals were present including the NRC project manager and a utility licensing manager.
Each session started with an introduction describing the purpose of the interview and stating that information collected was not part of an NRC inspection of their plant. It was explained that the purpose of the interview was to support the NRC review of an advanced reactor design (ABB-CE System 80+) by obtaining operating experience of the predecessor plant. A brief description of the use of operator input into the design review of the next generation plant was provided. As pan of the introduction, data on each operator's license and years of expenence was collected.
~
ne beginning of the interviews were left generally unstructured, thus providing operators with the '
opportunity to bring up any topics they thought were important. He review team had the list of '
topics identified above to guide later ponions of the interview session.
l i
t System 80 OperatorInterviews Page3 P
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t-r.
--2
4.
RESULTS The results of the interviews are summarized below according to the topic areas identified above.
Some additional topics are included based upon the data collected. While the objective was to identify issues, many operators offered solutions to issues they raised. These are included in the summary below for information purposes only. Such comments are provided for the designers consideration only. Allissues and recommendations below were provided by the operators alone (reviewers opinions are not included in this section).
While the summary below represents a combination of comments for all groups, a great deal of consistency was observed in the comments provided across groups,i.e, the same topics were raised from one group to another. This may have been the result of the shortinterview time, which led operators to focus on main issues. However, this consistency supports the robustness and generality of the findings.
4.1 Function Allocation and Task Design Issues h
- 1. Plant operations for routine transients (non steady-state plant evolutions), such as start-up, shut-down, and load changes, as well as more severe transients are difficult because of the need to integrate much information obtained from a variety oflocations and the need to involve many operators. Some examples of individual tasks that contribute to the difficulty am:
Heat-up and cool down rate limitations (this requires one operator just to log and plot information)
Control element assembly position control and verification Reactor coolant sy' tem letdown control s
Throttling of high pressure safety injection operation during its emergency operation The operators noted that better display integration and inemased automation may help them through these evolutions.
- 2. During unplanned transients, there is too much information pmsented immediately for operators p
to process. In addition, operators often (especially after emergency actuation) have to take manual control of many of the tasks that were automatically controlled (such as maintaining pmssurizer and steam generator water levels). This change in control modes alone is a challenge to the operators.
T 3.
per t rs have to remember (memorize) their initial mst trip actions and are expected to accomplish them prior to procedural checks. Aids shou: d be available to the operators for this purpose.
- 4. Reactor coolant pump seal leak off retum isolation - Under loss of seal injection and thermal T
barrier cooling, operators are requimd to manually isolate the seal within about one-minute. This has prompted management to place a relatively large sign on the control panel to remind operators to take this action when indicated. Failure to do so could lead to seal degradation, possibly escalating to a sealloss of coolant accident. Operators indicated that automation of the task of seal isolation should be explored.
p
- 5. Too much information has to be mentally calculated by operators that should be provided directly. Examples are:
Heat-up and cool-down rate.
Primary system leakage, and Calculation of the approach to criticality ("l/m" plots).
System 80 OperatorInterviews Page4
T 6. Operators need a better way to assess the status of the electrical distribution panel luring abnormal situations, especially during electrical problems. Because it is infrequently u:ed during such a situation, it is currently a very perplexing panel for many operators.
Q
- 7. Test and maintenance activities are associated with many LERs. Systems should be designed to be tested periodically without creating incidents. In particular, surveillance testing is a problem:
Dere are a great many tests and the manpower required to perform them is large.
Too many tests mquire auxiliary operator support for day-to-day surveillance.
(These should be capable of bemg performed from the control room).
Many tests produce spurious alarms and have provided unneeded confusion to operators.
Inadvertent actuation and isolation can and has occurred.
There is the potential to trip the plant and actuate emergency safety functions.
p
- 8. Main steam isolation valve (MSIV) operability stroke tests are difficult to perform without tripp.ng them closed. The valves are engineered to too-fine tolerances and easily close completely.
D
- 9. Mid-loop reduced inventory operations during shutdown are a problem. At such times, the ability to maintain forced coolmg flow through the core is mom difficult. Therefore, when the flow is lost, it will heat up quickly since it is hard to restore and there is less water to heat up.
y
- 10. Positive displacement pumps such as charging pumps are difficult to maintain and increase operator burden when they fail.
N cau. Push button lamp replacement is problematic because the removal and replacement oflens I1 se inadvertent actuation.
p 12. Several operators independently stated there should be a better way to depressurize RCS manually.
4.2 Alarms Issues p
- 1. The alarm system acts one way during normal conditions and another during transients (which is misleading to operators). For example, the diesel generator (DG) trips are restricted during emergency start and operation. If a non-emergency tri a comes in, the DG will not trip, but the "DG Trip" alarm still nngs. This is very difficult for tie operators during such busy periods. This occurs because the DG TRIP alarm is set off by any of 17 trip signals. However,in emergency-only actuation, any of 3 (e.g., diesel engine overspeed) will really trip the diesel..Yet if any of the remaining 14 signals occur, the alarm still goes off even though the diesel is not tripped.
i p
alarms can come in from the failure of one train. This is not the " conservative" thing to do in view
- 2. Some alarms have default conditions that make them misleading. All emergency actuation of the indications that are obscured when the alarms " default" in. For example,if one channel of 4 channel logic is lost, then the alarm default is on. Yet the alarmed condition may not exist (since actuation, for example, may require 2 of 4 channels).
h
. Nuisance alarms:
3 Too many relatively unimportant alarms come in during a disturbance.
No prioritization of alarms is available to assist operators in determining which alarms to attend to first.
System 80 Operator Interviews Page5
\\
Alarm filtering, such as mode dependency alarm suppression is needed. (For example, not having alarms come in which are appropriate to the current plant operating mode, e.g., start-up).
Some of the alarms going off as a direct result of surveillance tests should be -
eliminated (can bring in up to 100 alarms). Bypass of spurious alarms resulting from surveillance testing is desirable but requires a lot of operator's time.
Vendor specific alanns are in;luded in the CR, which have no operational meaning to the operators.
p
- 4. Master alarm tiles, which provide a single alarm for many signals, are pmsent in the CR. The specific alarms for these tiles are provided on cathode ray tubes (CRTs). The alarms are displayed as a scrolling list which makes the evaluation of alarms difficult. Further, no alarm buffer is -
available so when alarms scroll off the list they are lost from the display. Operators must go the alarm printer to see the alarms.
D
- 5. Noise resulting from the many alarms coming in after a trip is too great. Selective post-trip silencing of alarn.: should be automated.
p
- 6. There are many different alarm tones, the number should be reduced.
p
- 7. Many alarms on the boards are difficult to see. (An eye-level alarm panel might be better.)
p
- 8. The radiation monitoring system alarm system is an - tample of how to not design alarms:
The alarms are not prioritized.
a The feedback on acknowledgement is slow.
The tone is extmmely annoying.
=
4.3 Indication and Display Issues
{}
- 1. There is too much information provided to operators. Some ofit is needed but much is not needed and is distracting.
p
- 2. The use of engineering units which mean little to operators is a problem, e.g., "lbs-mass / hours" rather than percentage of full power flow.
p
- 3. Feed flow scales and steam flow scales am side-by-side but do not use the same scale.
N
- 4. General indicator displays in the control room are difficult to read:
V The small, uniform scales are too small to see beyond asm's length.
Scale lines am too fine for the discriminations operators have to make.
Indicator arrows are often too wide for the fine scale line.
Meter covers have become scratched and yellowed making some hard to read.
Static on the meter face can affect the reading.
The glare from overhead lighting puts a "bar" across each indicator 2/3 of the way up scale - right in the usual indicating range.
Power available LED lights masks readability and must be shielded'to be read.
D
- 5. Need better access to data. The direct meaning of data is not precise enough.
h
- 6. There is not enough information mgarding the secondary side of the plant, for example, an indication for feedwater heater level is not provided, p
- 7. Operators do not have enough capability to select parameters for display. Shouldn't have to use System 80 Operator Interviews Page 6
<s e
4 only " prepackaged" displays.
k
- 8. Mimics are important aspects of the control board layout. (Operators added mimics where they could.)
g
- 9. Rapid scanning of boards is essential to get overview of plant status. A selection of significant instmments (or digital readouts) with large, readable indications should be available for a person in the horseshoe (note CR primary boards are laid out in a horseshoe-shaped arrmgement) to be able.
to scan the boards and get a sense of the plant status and where it is anticipated to go. Currently, the annunciators are the only practical way to obtain an overview of plant status.
4.4 fontrol Device Issues
)
- 1. All push buttons look the same so it is easy to push the wrong one.
p
- 2. Placing identical feel pistol grip controls next to each other (reactor coolant pump and pmssunzer heaters)is a problem because you can easily grab the wrong one (shape coding and better separation of controls is needed).
r-
- 3. Large throttle valve (economizer isolation valve - moisture separation reheater steam inlet)
I switches (round buttons) have to be held continuously for more than a minute for the valve to open. This may restrict an operator from doing other possibly more important tasks.
b
- 4. Protection of controls from inadvertent actuation is important. Guards have been placed over several controls as a backfit.
4.5 Computers D
- 1. The computer system should be kept simple and " user-friendly."
g
- 2. The difficuly upgrading the computer system is a problem. The computer system should be state-of-the-art and be designed to be easily upgraded.
D
- 2. Delays in computer respones is a source of fustration to operators. Response time should be as short as possible.
4.6 Communiention Issues D
- 1. Auxiliary operators cannot be contacted in the plant approximately one-third of the time due to their inability to hear pages from the CR since there are many dead spots in the plant.
p
- 2. RF interference degrades communication. (Additional shielding is required.)
p
- 3. There is a need for additional locations in the plant to " plug in" communications equipment.
C O L
- 4. If the plant trips, the amount of communication is difficult for operators to deal with. The ability to " cut out" unnecessary communication lines is needed.
1 4.7 Procedures Issues
( 0 L-
- l. The procedure numbering system is cumbersome (procedures are designated by long strings of numbers and letters)
System 80 Operator huerviews Page 7
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-}
- 2. Procedures are difficult to work with especially in the CR during a transient. There is no lay down ama and portable carts have been used, g L.
- 3. Aids to follow procedums are needed.
4
- 4. Assuring current version of procedures is a problem
- 5. Number of proceoures for some evolutions is a problem, e.g., turbine start-up requires four O
separate Procedures (jL. 6. Integration between procedures, interfaces, drawings and equipment is a problem.
Q
- 7. Portability of procedums is very important. (Wouldn't want to see them on CRT.)
4.8. Control Room Layout and Habitt.bility
- 1. The control room is too large. It is easy for operators to become out of position and when in one location, it is difficult to see information on other panels. For example, CRT alarm displays cannot be seen from the rear position of the CR. Too much walking is mquired to perform tasks.
N
- 2. Emergency function displays and controls are not adequately grouped, which requires operators v
to move back and forth too much.
h
- m. The noise level in the control room is too high during a transient and adds a lot of stress and 3
akes communications difficult:
ESF actuated ventilation (esp. 2 trains) is an additional annoyance.
High-speed printers Alarms ringing constantly The operators become overloaded during complicated events and let the alarms ring.
p
- 4. I&C activities in the CR is very distracting (e.g., allow as much testing to be performed outside the CR, or on back panels, as possible).
p
- 5. There is a need to keep traffic down in CR.
N
- 6. CR floor is very hard and contributes to operator fatigue. Items such as carpeting would help u
minimize this problem as well as reduce noise.
4.9 Local Control Stations p
I. Remote shutdown panel:
There is not enough room to work The panel equipment should be similar to the CR equipment
'Ile panel equipment should have a mimic like CR.
a 7
- 2. The need to involve multiple LCSs forindividual tasks is a problem. More integration is needed to reduce the number of LCS activities that the operators must coordinate.
- 3. Space for handling procedures is need at local panels.
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4 s.
e f 4. Manual operation of steam generator atmospheric dump valves (ADVs)is difficult because of inconsistent valve operation with valves in close proximity to each other.
- 5. The capability for synchronization of the diesel on the bus should be available outside the control room. This can only be accomplished from the control room.
5.
CONCLUSIONS Founeen licensed operators and control room supervisors of System 80 plants (pedecessor of the System 80+) were interviewed to identify issues for consideration in System 80+ design and review. Due to the similarity in design between System 80 and System 80+, these issues and any other similarly derived ones, need to be camfully evaluated by ABB-CE to ensum they am addressed,if appropriate, in the 80+ HFE design. Since ABB-CE did not specifically interview currently licensed System 80 operators or include System 80 operations documents in their OER, it is especially impottant for CE to consider these items (and erhaps to further review System 80 t
operatmg expenence to identify similar items).
The applicability of a number of these current System 80 licensed operatorinitiated issues to the System 80+ design needs be evaluated and where appropriate their resolution should be identified.
The issues tracking system should be used to ensure the consideration and resolution of unresolved applicable issues in the design process.
In addition, since the time available to review the SCSS abstracts was limited, a thorough analysis of the LERs could not be performed as part of this effort. However, it appears from Table I that there were many events related to task design / performance. Twenty seven percent of the actions involved licensed operator personnel,23 percent involved operation activities, and at least 13 causes were identified as HSI caused. A more detailed analysis of at least a select group of the original (full-text) LERs, may be warranted for the System 80+ design.
6.
REFERENCES Fuld, R. (l2115/92). Human Factors Program Planfor the System 80+ Standard Plant Design (NPX80-IC-DP790-01, Rev 01). Windsor, CT: ABB-CE.
Higgins, J., & O'Hara, J. (March 1993). Review of the ABB-CE System 80+ Operating Experience Review (Draft Technical Report E2090-T2-5-3/93). Upton, New York: Brookhaven National Laboratory.
System 80 Operawr interviews Page 9
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