ML19308C363

Human Factors Aspects of Nuclear & Fossil Fuel Power Plant Maintainability, Proceedings of Human Factors Soc twenty-third Annual Meeting,Nov 1979

ML19308C363
Person / Time
Site:	Crane
Issue date:	11/30/1979
From:	Parris H, Parsons S, Seminara J ELECTRIC POWER RESEARCH INSTITUTE, LOCKHEED MISSILES & SPACE CO., INC.
To:
Shared Package
ML19308C359	List: ML19308C358 ML19308C360 ML19308C361 ML19308C363 ML19308C364
References
TASK-TF, TASK-TMR NUDOCS 8001220840
Download: ML19308C363 (5)

Text

_

~

sw.

y PRbCEEDINGS (OFL THE MUMAN j FACTORS f SOCIETY 23rd ~ ANNUALS MEETING " NOVE'MBER.1979 j

~

I

.HINAN FACTORS ASPECIS OF' NUCLEAR AND FOSSIL 1 FUEL POWER PLANI MAINIAINABILITY 3.

fJoseph L.:Seminara.

.Stuart 0. Parsons

Lockheed Missiles and Space Company-Sunnyvale, California' Howard L. Parris~

. Electric Power Research Institute Palo Altog Calffornia

-ABSTRACT

.. --Fi}e nuclear.and four fossil fuel power plants were revi,ewed'in terms of: human factors aspects of maintenance activities. It was found that the human factors discipline can make a substantial contrilotion. to the design of. facilities, equipment, procedures, work aids, training programs,

' cnd protective gear... There is an acute need' for human factors design guides and standards tailored

. to the specific needs of the power industry.

INTRODUCTION In'1975_the Electric Power Research-Ins'titute and extensively photodocumented. Selected

- (EPRI) sponsored a study entitled " Human Factors.

on-going maintenance tasks were tracked syste-

- Review of Nuclear Power. Plant Control' Rooms.

matica11y by means of standard task analysis A Lockheed human factors; team reviewed five

. proc'edures. In addition to the primary,

. cperational_. control rooms and ' their correspond-

' con tacts with maintenance personnel.

.ing training. simulators.- It was learned that.

cestings were held with. plant management, train-

[.

l much couldc be done. to improve the operator -

ing directors, operational per;onnel, radiation cent.rol room interface and the results of this protection technicians,' quality control per-initial effort were documented in a 450 page sonnel and designers from major vendor-($eminara, Gonzalez 'and Parsons,1976) report organizations._

published by EPR1 and sumarized elsewhere

"(Seminara,. Pack, Gonzalez a'nd Parsons,'1977).

FINDINGS In-the course of the control room study it became Facilities cpparent that it was equally important, in J the interest-of improved plant availability, It was found that each of the five nuclear to consider human factors aspects of power plants and, to a far lesser extent, the fossil plant 1 acilities and equipment designs from plants have underestimated required manning f

L e maintainability. standpoint. Accordingly, levels for maintenance activities.' Workshops in 1977, EPR1 contracted with Lockheed for a designed for.an anticipated fif teen-man review of-five nuclear and four fossil fuel mechanical maintenance shop now house seventy

plants to determine the extent to which such to eighty men.

Nuclear plants designed for a

. plants had been configured and equipped to total workforce of 150 men now house about facilitate required maintei.ance activities.

four hundred and the numbers keep growing.

This growth could not have been anticipated METHOD 01DGY when the nuclear plants were design'ed some fifteen years ago or more since no one An initial orientation visit to three plants could then predict the need that has developed L

was conducted to develop a preliminary -

for' 1arge plant security forces, quality control l'

overview of maintainability concerns' and.

personnel, and the extensive health physics -

l proble= areas. Based on detailed' discussions staffs. Nuclear plants were basically developed.

[

vich caintenance peronnel and plant tours the on the design-foundation then existent for

subject ' matter was obtained for developing fossil plants. In any case, the result -

i data - gathering tools:. structured interviews, is overcrowded workshops, a hodepodge of

- hu=an' factors evaluation checklists,. task scattered " temporary" structures, a constant

- cualysis formats, critical incident approaches, reshuffling of plant space, or new construc-cond photodocumentation procedures.;

' tion to accomodate people. - With facilities already strained to house in-plant personnel,

A representive mix of nine sites was investi-the' problem is further aggravated when two.-

gated by a _ five man study.teami with five to

. to four.hundred outside contractor. persennel

~

seven days; spent atj each plant. ~ Eight to ten are added to the work force during major

^

- maintenance personnel were interviewed at-

' outages.

' cach-plant with interviews averaging four hours teach.v~ Reported maintenance problems and,.

Environmental Factors crecorded maintenance errors were investigated.

8001220

-I

hk khbk Oj[ N [ v 2

((

Q>T"

[~

N

]""~

T g

Wh:. ;, Wm.. ~. :

,3 g n - ;... :

Mhaouer}plartslcff;riatvari:ty of envirsc-y

, f as_13 r:pairosal dfaning lprettetive gtreets r o

4$ymental;hasardtcad strscoes whithJptsfoundly).

' fend : air bottiss,(sco figura 3)/

s g

~

i MMfcffste?thi_natura:ef maintenares cctivities.1 ~ ; t f Q Radiation protection maylrequireiseveralt

,' '. % l Movement of Men" ant Equipment r

gw 71ayers' of protective"garmentsiplus fu11(...

W ' face: masksiand; air-bottles j strapped;to,the back' ;

she study 7 examined; facility de. sign-from

~

~? Both nucleariand fossi1 Tylants1 offer high

t'empera- { the standpoint of the ability. co, move men -

% fturel work 1 situations with' temperatures..i.

fand equipment vertically and horizontally

~

~

ithroughout the plant-in accomplishing--

- M betweenT100-175. degrees not. uncommon.D No!

'; maintenance -operations.. Some problems 2 $fullyfeffectiveltemperature fprot'ection garmentsj

s uncovereC includedb i

%" Qcra;available./problemsf ar;e even; more; acute:

)

iin multi-stress, environments? e.g? high noise,i~

' radiatfan and hishitemperature work l sites.

c 5 Insuf ficient'and unreliable < elevators

~

orlthe use of personnel elevators -

$Nw 1 t;

. ob$1'ousbneed for_the development :

~

where cargo' elevators:are required.

There ~is 'an.

s 0 jycilimprovediprote_ctivefgarments;forfcombatting!

gn? h:st' and radiction singly,andlin combination.3 os Inadequate provisions and clearances:Zor jiAlso 2 facility de' sign improvements. arelneeded ; '

. rigging and hoisting.;

f to.offor better-protection. 3For exampleA in-1 s

' 3 3 ncne. case thefmain traffic path 1through the fo iInsufficient; crane coverage and' inadequate 7.d # (plant exposed all' personnel.to. noise t

1evels

- escape provisions.for crane operators.

} g, (ofJ110-115idb. 7 Ear l protection-was readily

~ 21 ((available but it; was:a nuisance 'totinsert '

oD Excessive -use of wooden scaffolding for" g [eariplagsisimply,to dash into the> vending?

lack of-permanent _. access : provisions. :

Wt Emachine areas." Sound.barriersJare feasible' g'

(and are_being considered.J At some plants /

(Sometimes limited ' aisle clearance is provided-

~

~

aquipment systems may..be-unsheltered creating' for moving highly expensive and easily -

]gjg sc11matic. problems for repairmen. It may-be-

. damaged pumpiseales Restricted passageways

.nscessary,to-erectitemporary shelters overJ also ' limit the use of vehicles or carts' for

^

ithsivorklalte1befo're

the job' can proceed.1 transporting heavy motors or pumps thereby1

<p:

icther hazards in the environment include

' taxing human strength capabilities. 'In other

[

-lcausticiand_ acid solutions, oil spills,'

_ cases, traffic is routed past radioactive R

iand< steam: leaks.

_ plant elements increasing personnel exposure.

i Access, to' Eculpment -

Codina~and Labeling' j

n

= EThs mos't univershi complaint voiced.by maint-Standard ^ coding and labeling practices generally

enance pers.onne111s. the11ack of act

ess to the utilized.in the aerospace connunity have not t

s Iequipment being maintained. Insufficienc,

been generally adopted in the power industry. -

~

~

' clearance around motors,' pumps,~and valves' Label, tags taffixed to valves and other

for removal-replacement operations is 'too -

components generally lack sufficient contrast..

Hoftenithe case / Inl isolated' instances, Sometimes they may be absent because they were is

- (in'orderfto' gain access;to'a malfunctioning 1 not replaced when the original component was-3 E

n nit, an operable ladjace' t unit must first be ~

replaced.' Color coding of different lines N

u n

fM idislodged.11Tpon occassion, entire _ walls and systems is' minimal with only the fire.

f inust be knocked ldown and rebuilt for. access.-

protection (system _ highlighted in red. A Z

1Hany;co=ponents..are located twenty,to forty-common problem:is in differentiating between u

fest above floor.levelninviting repairmen-two ' identical units -in multi-unit plants.'

• J

. x to ) scramble j over: pipes' and ' assorted precarious Maintenance men may be dispatched t'oa J 7 parches. ;The11ack' of work ~. platforms also deactivated unit ' on a repair assignment. but

~

[

{ invites damage: to equipment as the repairmen

. find their. way. instead to its twin which is -

iusa any convenient-foothold-(see-figure 1).

active <and potentially dangerous. labeling d

[, EAsithe n'eed?for better access provisions.-

identification. deficiencies are too often f sisa revealed from fjob-to-job,' the maintenance 1 corrected only. after an1 operational mishap.

M, organizations: erect work platforms as shown W "'.,in figurec2.T onefplant,-over the_pastlfive:

Productivity and organizational Interfaces H.6 : yea _rsJ has-kept:aicrew of men.busyisimply-1 A.recent work sampling study conducted in a' l ibuilding platforms;to work areas end.their 9workis;not_yetfcomplete.

nuclear plant _ revealed that only 25% of_ the,

. time worked by maintenance? personnel was--

^

[ThIreLarUeconosiciconsequencesitoithese.

- hands-on main?.enance. ; The study was repeated idasign deficiencies.jMaintenancelsupervisors :

in the following year and 'this ' number moved '

s

'W Qastimate that',ivithridealior unrestricted fupfto'29%. This; contrasts with a' generally-

• JaccessIto e'quipmentfsystemsfan'overallf (accepted comparable figure of 60% -for1

~

zi isdvings;or >30% maintenance timeLcould bei

. fossil plants..

f /ac'hieved.37he designers ofsnuclear. equipment.

@ Nystems tobviouslyTdid notihave. before"them f.

..The =1ow productivity value is attributable to i the model of a 95th percentne

- a variety; of factors. characteristic of -

~ m m;anthropometric 5W '

y '

> JC

• A,

y 7

,g; M g chA 7,'N

?

,m s *

,___7,.

L* ~ 7 *

• j '5{ Mg '

& .M.'*.R r

~

y' k

4

~

p.

j

?

D

$. O k'

?,

~

j I

l

/9 : %,,.?

"i.

gg.'

r,/4 t-

" ~ ' '

k-f j ~,n'1,Jg

~ ~~

s -

['{ 's ',,,.

p N. ;it "a

'. :;d

' k dh,p. m,_. '. *

(

E' h h, m&{

s

(.YT" * $' 5@

a/ tj IT'

[.j p

j-q.!.W(#

I

jj)d -

7

.[.f l

k IN Y!$G [j p{/

'9' N

.'7*91Q -

isj '

I M1

.^R

1. ~^~

w.__?,

1. .{,'

'h-

~

)

j i

en w'.n,.

m 8

S-Q i

l J

7_ - --

g 1*

w a

1 4

3. 'TLD

.iY?%

\\

M$*1% _~. I*

j u.

g.

FIGURE 1.

REPAIRMAN STANDING ON' AN AIR DUCT FIGURE 2 MANY WORK PIATFORMS NOT INCLUDED IN FOR LACK OF A CONVENIEhT WORK PLATFORM.

THE INITIAL PIANI DESIGN ARE SUBSEQUEhTLY ADDED BY MAIhTENANCE CREWS.

(

l l

9.,- n yr, > ~ -

~

,y--.

p x,#EW'M "i'

f a,..n.-xy$

e a-

'/,.

i N -"

7(

h-)I

~ [!' _ _

i k,

' ^^

v g

2 L^...

FIGURE 3.

95TH PERCEhTILE REPAIRMAN ENCUMBERED FIGURE 4.. WATEK BARRIER DEVISED BY OPERATORS BY PROTECTIVE GARMENTS AND AN AIR SUPPLY.

TO ALLOW MONITORING OF ACTIVITES IN RADIOACTIVE ENVIRONMENTS WITHOUT EXPOSING OBSERVERS.

3 i

.,_,.,,_._,,,.~,,.p..----._,nwa

y3(

~ ^ ~ - ~ --

m.

y y

- y, fg e---

- C u ;, MM., l a m:[.. ?E..

. -[

N.

.;M.

~

$.B auclear pl nts(that impede work lct<cvery turn s

^J ia Auch crocs.!_

s o /Increa31: gly string %tt p1=tzescurity;rs-

• [quirements7any initially! delay entrance

' Tools and' Test Equipment

_ GM tAthe9plantQMain.tenanceTvehicles 'are 7 Tools and test. equipments ~ are j generally 'off-tid-h 7_

is

apain-locked 'at the ateoring wheel and. require?

.va, guard;to arrivefwith alkey'.H Manyl plant;

. shelf itemsland. are of ten: inappropriate - for j

use -in radioactive work ~ environments. ;

i a fcr:as have been2 isolated and secured.

^

M Accessiis~again preventedf until a! member of-3

Surfaces whichl trap radioactive particles:

. M thp guard'forcefcan;be spared. to unlock thei cannot readily be-decontaminated.;;Such

~ f door-or: gate?

's

~

' tools,.e.g. with knurled surfaces,cfind'

~

a.a their way;into' radiation: waste barrels.and - the JPinnt operators'.must clear 1*nd tag equipment;

' utilities.-lose : thoussnds of dollars a year

in _ this way.7 est' equipments that, become T

, g os 'a prerequisite ' to repair ' activity.' '

jNaintenance personnel.are frequently..

Econtaminated must remain.within " hot" areas

/d, layed:because of-this dependence on plant:

land aisleway's.become cluttered with roped-off

_ Japerators.:.The Operations Department'is'

" hot" equipments. There is aineed'for. '

sof ten short-handed,Eespecially during-outages.

,researchidealing.with tool designs-(e.g.

s. i, long-handle tools).for use in radioactive-

lJNuclear' plants l maintain Health Physics.(HP) -.

- envirorsnents Lto promote ease of deconta-4

' (cr/ Radiation-Protection staffs to' safeguard:

mination and to' provide maximum separation -

i

~

1personnelifrom radiation' exposure.~.Before:

of men and radioactive sources.y 'There may=

1

{maint'enan'ce work can proceed -in a radioactive-Lbe ;some special applications for robotics if -

~

I !crea, an1HP survey must be performed to,

'the plants are designed from the outsetwith this

~

>. idttermine' exposure levels, the type ofi possibility in mind. ' At one' plant, one -

~

Jprotective gear required.1and,to prepare:the ofl the operators' developed and patented '

o

- e4 must be' issued'and the: exposure history of..

"a special glass encased water barrier (See

} site forL work. :. Radiation-work permits -

= figure 4Fwhich can' be ~ incorporated into l'

personne1 ass'ignedLtoldo the work must be..

concrete block. radiation protection walls.

'l

~

reviewed. to ensure.that' quarterly exposure -

Such devices allow support personnel to q

.^ - ilimitsf are not being exceeded.' HP requirements' observe maintenance and operational task's

also frequently delay -the onset 'of work and ;

occurring;in radioactive sites without.

~

1mayfseverely limit the maintenance manager's' exposure to the onlookers.

~

floxibility in assigning.' specific personne1'

< ~ '

' yto? job's solely-on the basis of special Communications i?

sexperience or skillLlevels. m In an earlier; study of control room operations

- Another; organizationa1 ' interference that:

- (Seminara and Pack' 1978),: it,was found ~ that smay delay work relates.co'the Quality' over 80% of the operators. interviewed -

fAssuranceDand Quality Control' function.

reported problems and. frustrations with the 4

> QA/AC personnel introduce HOI.D POINTS 'in

- plant: consnunications System. Simularly.

(maintenance procedures' associated with, 757. of the nucle'ar maintenance personnel J

-so-called / safety-related' systems. At such' interviewed indicated problems of varying

- p'oints in the evaluation' of the maintenance types. and severity. ~ By way of contrast,

.--job QA/AC_ personnel must, be. called to

.less than a third of the fossil plant-i ths 'seene; so tha.. their inspection' functions

. personnel were experiencing such problems.

can

be accomplished. - This _ introduces another In order of frequency, the problems reported J

7 potential:for delays.'-

f fall into the following categoriesi (1)-

~

Insufficient capacity-on existing communication I

%ny of the above interferences entail systems,- (2) Insufficient coverage of the

/considerableEassociated paperwork and a plant with adequate communications devices,

cemmon

complaint is that maintenance foremen

'(3) Inability to' utilize consuunications equip-E lend' supervisors are-spending an inordinate

ment effectively.while wearing protective

cstount.of time lin:their ' offices overseeing gear, -(4) : A need for alternate or more this paperwork 11nstead_ of supervising the effective. devices,' (5) Inability to hear or

~

make oneself understood in exceedingly high

- :: Jobs 1 going on'in the plant.

noise environments and (6) Unreliable or

[i

( Tha many built-in delays 'to accessmodate interrupted: communications.

L

- : vital; interfaces with other organizations.

(cnd to. comply with regulatory ~ requirements Training.

+

_ Tara frustrating to maintenance personnel, s

cspeciallyfduring7the hectic pacef mposed The utilities' invest most of their training -

i ibudgets on control, room operator:($100,000-iby outages.1 Each;dayithat-the, nuclear plant ~

-to 200,000 per operator)' training. There is

is iff-line

costsi$300,000.to-$500,000 inl

~

~

t J t'rms of replacement) power. j While.it was -

nowhere nearfsuch a committment to the training i

Dbeyondiche scope of this study.to delve'into.

'of maintenance personnel with thr possibic E 2cignLrequirements to expedite, for example,'

texception~of instrumentation and control' d

Uv 'ths interface between maintenance;and Ltechnicians. The need for additional mainte--

'" ; ; Hrcith; Physics',1 fo11ow-on. work is:recornmended

.: nance training is quite' evident.. First, there

w a-Q, v

r-4-

+...,e Se w-,..,_,,_-,,-,,_.

e.,n.

.%e,,e,-yvy.

,..,--,.,,-m,4m,,

i

~~'

' ~~

~ ~~

y 47

' tio a con: cent' bstt12 to kup r: dict icn exporura Control Room', NUCLEAR SAFEIT, Vol.18, 1,1cvalo. c3 low cd rocaonably echi:v bla. (ALARA).

'No. 6. November-December 1977.

- There is an obviousj relationship between'

~ '

repeirman ; skill levels, -thit timei to do the' job, -

Seminara

.'J. L. and Pack, R. 'W., Cocaunication

= end radiation expos,ure level.. Each MAN / REM Needs'of the Nuclear Power Plant Operator,

l of radiation exposure costs the utilities

'IEEE Power Engineering Society Summer Meetinga

cpproximately $5,000. fSecondly,fslow or Proceedings. July 1978.-

ineffective maintenance translates into increased

. down-time and loss,of revenues. Consequently,.

~ in appreciation of the impact' of maintenance

• ,M

' = ' :)

~

y.

perfor=ance. times, there is a trend towards jM g

> Mi[ [fi the use of mockups for rehearsal of tasks to 1

n l~

'I h{"i s

be' conducted in radioactive environments-

~ ~

[

• .i l (3 - _

=(see figure 5).

3[f

. < $p

.r.

Design Practices -

g;w -

4 'c h

/

q;

~

It' was. apparent 'from the review of power plant'

,/f 7, i QQN M.

i>- g-h6 H S ~u yp dasigns that much could be done to tailor-

' )%!-M N SY future power plants to the abilities -and limita-pA%- Ao d@f

~,

tions of the men who must service and repair t

[

d

~

.them. : Contacts with. design organizations

. u,'.h::, - :: : - ~ g j reveals the lack of any formal human factorg 1

Q angineering guidance or design standards. On y_,

u those occasions when the utility has been willing

..< b -. r -[# ' {L

)

i Jto spend the extra $1-2 million for a scale p=-- r model (see figure 6) during the ' design process, 1

as_um

.k W~ ' - )

then access: to equipment 'and major interferences

^'

ware gros' sly. checked. However, such scale models are not adequate for design verification FIGURE 5. M0CKUP FOR MAINTENANCE TRAINIl0

' studies to evaluate the more important man-

~ "

\\

Y-m: chine interfaces. ' Full-scale mockups 3

M h

k g p pM" M

. or prototypes are required with suitably gtrbed men in protective' gear used as test 9,, a j [U _ n 4 subjects. It'is.also necessary to simulate EM'

,b1 5

- y heat, noise and illumination aspects of the

g_Q '

,. o,

work environment.

CONCLUSIONS The nt ber of hu:ran factors specialists involved 4;~'*'"

' ~~

- -=

9'

.-in the design of nuclear power plants is extremely

.*h f p iW h[

small. This situation is expected to change p; __r; rapidly in the near term.

Largely through the

[7 O g--

.r-- d* ga e

efforts of the Electric Power Research Institute, f,

4.*i. e i

an awareness is building of the need for ll

- !)

'g specialized hu=an factors attention in power

' plant. designs,' control room operations, proce-

%~@;-.%(],]"" *

'l 1 dures, training programs, and performance measure-W asnt approaches. There is an urgent need for.

.: M.k, _su

g b

human factors ' design guides and standards

'+

7~ '.

g tf to i= prove can-machine' interfaces in both maintain--

g g, g,g g d '"j ing and operating power plants. There is also a corresponding need-for human factors

. ~,

3 3.!?iT* * *

E w

d 1 specialists. co " infiltrate" the power industry

~~ii d ;

2.

~ y p}.

Lin much the'sa=e ~ fashion that this was accomplish-ad 'af ter W II in the' military and space programs.

)

u w

m.a

~

b h_

,~

Seminara, J. L'..- Gonzalez, W. R. and Parsons,

- ". - ~ ~' W _

_ c_: m y,,_

j

.S.

O., Euman Pactors Review of Nuclear Power -

~- 7 ge;

~

-Power.Research: Institute, Palo Alto,'CA.

Plant -Control Room Design, EPRI NP-309, Electric

~

FIGURE 6.

SCALE MODEL USED IN DESIGNIID POWER Siminara, J.

L., Pack,- R. W., Gonzalez, W. R.'

PLANTS. NOTE THE M M EL MAN.

icnd JParsons, Si 0.,

Human Factors in the. Nuclear 5

.