ML20126B898
| ML20126B898 | |
| Person / Time | |
|---|---|
| Site: | 05000447 |
| Issue date: | 06/10/1985 |
| From: | Sherwood G GENERAL ELECTRIC CO. |
| To: | Thompson H Office of Nuclear Reactor Regulation |
| References | |
| MFN-085-85, MFN-85-85, NUDOCS 8506140242 | |
| Download: ML20126B898 (7) | |
Text
.__
GENERAL $ ELECTRIC NUCLEAR ENERGY BUstNEss OPERATIONS GENERAL ELECTRIC COMPANY e 175 CURTNER AVENUE o SAN Jose, CAUFORNIA 9s195 June 10, 1985 ftFN-085-85 U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D.C.
20555 Attention:
H. L. Thompson, Director Division of Licensing Gentlemen:
SUBJECT:
IN THE MATTER OF 238 NUCLEAR ISLAND GENERAL ELECTRIC STANDARD SAFETY ANALYSIS REPORT (GESSAR), DOCKET NO. STN 50-447; EMERGENCY RESPONSE INFORMATION SYSTEM (ERIS)
Reference:
1)
Letter, G. G. Sherwood to H. L. Thompson, "In the Matter of 238 Nuclear Island General Electric Standard Safety Analysis Report (GESSAR) Docket No. 50-447; Emer0ency Response Information System (ERIS)", May 9, 1985 Enclosed is information pertinent to the resolution of the open item on " clutter" related to the General Electric Emergency Response Information System (ERIS) displays. is a letter from our human factors consultant Anacapa Sciences, Inc. which provides additional information regardin ERIS displays discussed in Technical Report 550-1 (g the Anacapa evaluation oftrans The letter establishes that the human factors specialists who assessed ERIS:
1)
Concluded that a large amount of information is presented but all of it is needed to facilitate operators' decisions.
2)
Did not find the display screens to be cluttered.
This has been discussed with the NRC staff.
As a result of comments by the NRC Human Factors Specialist (L. Betracchi),
General Electric has reassessed the abbreviations used in the RPV and containment control system status indicator text.
It was found that the total number of letters could be reduced by about 20 percent without compromising the usefulness of the displays.
The RPV display using the revised abbreviations is shown in.
!DR 47 F
PDR 1
1 \\
\\
1 GENERAL $ ELECTRIC Mr. H. L. Thompson
}
Page 2
[4 l
Considering both the assessment of our human factors consultant and the input from the NRC, General Electric concludes that modifying displays as shown in i is reasonable.
Accordingly, General Electric is prepared to agree to this change for GESSAR if this will resolve the clutter issue.
l If you have any questions or comments, please contact H. C. Pfefferlen on (408) 925-3392.
Very truly yours, Glenn G. Sherwood, Manager Nuclear Safety and Licensing l
GGS: cal /K06068*
cc:
L. Beltracchi (NRC)
D. Scaletti (NRC)
L. Gifford (GE Bethesda) l l
l I
i
Mr. H. L. Thompson Page 3 GGS: cal /K06068*
bec:
A. L. Bashford C. F. Christensen J. E. Klimaszewski W. J. Roths R. C. Stirn J. J. Post K. E. Gregoire H. C. Pfefferlen D. L. Foreman R. L. Gridley R. Villa J. F. Lesyna
ATTACllMENT 1 c m,4.-
APR 41985 Y
Y ANACAPA SCIENCES, INC.
W vv riu n e,.
2 April 1985 Mr. W.J. Roths, M/C 213 Manager, Electronics and Computer Systems Engineering
(
General Electric Company 1
175 Curtner Avenue l
San Jose, California 95125 l
l
Dear Mr. Roths:
This letter is in response to Mr. Keith Gregory's request on 29 March 1985 l
for additional information regarding our evaluation of ERIS displays, which was reported in "lluman Factors and Performance Evaluations of ERIS," Anacapa Sciences, Inc., Technical Report 550-1, dated July 10,1984. Specifically, addi-tional comments were requested on the issue of " clutter" in the RPV Control displays (original identifying numbers were 113-123) and the Containment Control displays (original numbers were 125-130).
The generalissue of display clutter includes at least the following compo-nents: amount and necessity of the information displayed, degree of display integra-tion, familiarity of the subject matter to the intended users, and the degree to which parts of the display can be scanned individually to extract specific informa-tion. Each of these component issues are discussed below.
I One measure of clutter is the degree to which too much information, some of which is not necessary, is presented in a single display. While the ERIS displays in question each present a large amount of information, each item of information contributes to an operator's quick grasp of plant conditions--one of the primary purposes of a safety parameter display system like ERIS. These displays have already been streamlined to remove unnecessary detailin the time trends and She status bars; each of the remaining items of information is operationally impor-tant to the range of situations that would require use of ERIS. Reducing the current amount of information on a given screen would require the addition of other screens, which would increase the operator's search time for pertinent information and would impose additional operator memory requirements, to relate information from different screens.
Another measure of clutter is the degree to which displayed information is poorly integrated. A display is considered poorly-integrated when the intended user must consciously work at extracting important information and important relationships among different items of information. A display is considered well-9 e
P. O. DRAWER Q e SANTA BARBARA, CAllFORNIA 91102 e 901 OLIVE STREET e (805)966 6157
i t
Mr. W.J. Roths 2 April 1985 Page Two Integrated when it matches the cognitive processing of the intended user so that key information and relationships are evident without extensive searching, remem-bering, and thinking. Objective quantification of this measure is elusive. Descrip-tively speaking, however, well-integrated displays generally have the following features:
I
- All of the information required to complete some important decision or action is located on one screen, not distributed across several screens.
(Achieving this goal sometimes requires the presentation of a relatively large amount of information on a single screen.)
e Information is not presented in a large number of separate windows.
e items of information are appropriately coded as symbols or words and appropriately juxtaposed to facilitate decision or action sequences or to facilitate the extraction of important relationships among items of information.
Two human factors specialists, who were concerned initially about the possibility of clutter in the displays in question, quickly discovered the good match between the information that was displayed and that which was required to facilitate operators' decisions in responding to simulated transients. Experienced operators who represented intended ERIS users did not report clutter as a problem with these displays, though given specific opportunities to do so.
The intended user's familiarity with the subject matter represented in a display must be considered in assessing issues of clutter. While displays for the general population of non-experts (e.g., automated bank tellers, airport flight information displays, etc.) must be very simple to transmit their messages unambig-i uously and quickly, displays for trained experts (e.g., air traffic control displays, tactical warfare consoles, etc.) can present somewhat higher densities of informa-tion and still be considered uncluttered in the context of the expert user. Somewhat different standards must be used for assessing clutter in systems to be used by experts than in systems to be used by non-experts. While it is not suggested that system developers can rely on expert operators to sort out information in poorly-designed displays, it must be noted that human factors engineers cannot use the general population as a reference for assessing clutter in displays for special populations. As discussed above,' two human factors specialists soon realized the good match between the displayed information in ERIS and the operators' task requirements.
~
A display may be considered cluttered when the intended user trl~es to scan a part of it to extract some specific item of information, but finds it difficult
i Mr. W.J. Roths 2 April 1985 i
Page Three 1
to do so because other items of information interfere. Such interfebence may be due to the number of items of information; their placement in the overall layout; or perceptually-confusing symbology, terms, fonts, colors, or intensities used to represent the items. During the assessment of ERIS displays, neither the experienced operators nor the human factors specialists found this type of clutter to be a problem. While the above-referenced report discusses some problems in the selection of codes for certain types of information, these problems were not manifested as clutter per se.
In summary, the human factors specialists wh'o assessed ERIS did not find the RPV and Containment Control display screens to be cluttered. In fact, compared to several other safety parameter display systems extant during the period of the assessment, these screens were generally more streamlined and easier to comprehend in the ERIS system than in similar screens for the other systems.
Sincerely, ANACAPA SCIENCES, INC.
(Avh Robert Dick, Ph.D.
Principal Scientist RD/bg I
e4
.d e 4.
e e
423 RPV CONTROL--FR/ TEMP
'c"'"'
E IIH >TAF.
RPU LEVEL R UTR RPU PWR PMP g E
E IH s
CHDS/FU EAVAIL PR AVAIL RUN E 400 4 TRIP HI 52E E WTR RPU PWR PMP I 220-CRD EAUAIL PR AVAIL RUN I 0FFl l
l 40-4 SCRAM LO 9I PMP UTR RPU PWR RCIC l AVAIL E
PR HA
-162E HPCS l AVAIL E
PR AVAIL RUN E
-320_g..g.... 0
)
lg${t plP l
RPU PRESS E IPSIG LPCS I
U L
0 l
l 3
1500 l
4 P0OL LD E
I UTR RPU PWR PMP E LPCI EAVAIL PR HI AVAIL OFF I MMN I
l MSIU l a
SHTDN CLG RPU PWR PMP COOLING AVAIL PR HI AVAIL OFF 500-4SRV LIFT 1103E 5
( 100' BPU 995 l
gOfL AbNfL l
GROUP l 4
RWCU 0
-10 (MIN) 0 TURBINE E CL6 UAC H.PWR ULU E CONTROL I AVAIL AVAIL AVAIL OP E
RPU TEMP E E 'F TURBINE E CL6 UAC H.PWR ULU l BYPASS EAVAIL AVAIL AVAIL OP s 450-MSL l
CLG U.PWR ULU g l
SCRAM l 300-DRRINS E
AVAIL AVAIL SHT E CLC l
RUAIL AVAIL OFF I O
~
_30 (MIN) O
- h
~
~
E0MPLETE i
s'
.