. 1..Will.the.corrective.action.prevent.recurrence?
. 2..Is.the.corrective.action.feasible?
. 3..Does.the.corrective.action.allow.meeting.the.primary.objectives.or.mission?
. 4..Does. the. corrective. action. introduce. new. risks?. Are. the. assumed. risks.
clearly.stated?.(The.safety.of.other.systems.must.not.be.degraded.by.the.
proposed.corrective.action.)
. 5..Were.the.immediate.actions.taken.appropriate.and.effective?
Change Analysis (Use concept for all cases)
Use For
Use all applicable
analytical models Use scaled down methods or informal analysis No
Yes
Serious or Complex Occurrence
Barrier Analysis (Built into MORT) Complex Barrier and Controls
(Procedure or Administrative Problems) Obscure Cause
Organizational Behavior Breakdown
Events and Causal Factor Charting and/or MORT
Human Performance Evaluation and/or MORT Kepner-Tregoe Problem Solving
and Decision Making Thorough Analysis of both
Causes and Corrective Actions People Problems Multi-faceted Problems
with Long Causal Factor Chains
FIgure 8.1 Summary.of.root.cause.analysis.methods.flowchart..(Source:.Courtesy.of.the.
United.States.Department.of.Energy.)
tABle 8.1
summary of root cause Analysis methods
method When to use Advantages disadvantages remarks
Events.and.
Thorough.analysis None.if.process.
is.closely.
followed
Requires.HPE.
training
Kepner-Tregoe Use.for.major.concerns.
where.all.aspects.need.
Source:. Courtesy.of.the.United.States.Department.of.Energy.
tABle 8.2
cause code categories
cause codes
. 1.. Equipment/Material.Problem:
. a.. Defective.or.failed.part . b.. Defective.or.failed.material
. c.. Defective.weld,.braze,.or.soldered.joint . d.. Error.by.manufacturer.in.shipping.or.marking . e.. Electrical.or.instrument.noise
. f.. Contamination . 2.. Procedure.Problem:
. a.. Defective.or.inadequate.procedure . b.. Lack.of.procedure
. 3.. Personnel.Error:
. a.. Inadequate.work.environment . b.. Inattention.to.detail
. c.. Violation.of.requirement.or.procedure . d.. Verbal.communication.problem . e.. Other.human.error
. 4.. Design.Problem:
. a.. Inadequate.man-machine.interface . b.. Inadequate.or.defective.design . c.. Error.in.equipment.or.material.selection . d.. Drawing,.specification,.or.data.errors . 5.. Training.Deficiency:
. a.. No.training.provided
. b.. Insufficient.practice.or.hands-on.experience . c.. Inadequate.content
. d.. Insufficient.refresher.training . e.. Inadequate.presentation.or.materials . 6.. Management.Problem:
. a.. Inadequate.administrative.control . b.. Work.organization/planning.deficiency . c.. Inadequate.supervision
. d.. Improper.resource.allocation
. e.. Policy.not.adequately.defined,.disseminated,.or.enforced . f.. Other.management.problem
. 7.. External.Phenomenon:
. a.. Weather.or.ambient.condition . b.. Power.failure.or.transient . c.. External.fire.or.explosion
. d.. Theft,.tampering,.sabotage,.or.vandalism
Source:. Courtesy.of.the.United.States.Department.of.Energy.
A. systems. approach,. such. as. Kepner-Tregoe,. should. be. used. in. determining.
appropriate.corrective.actions..It.should.consider.not.only.the.impact.that.actions.will.
have.on.preventing.recurrence,.but.also.the.potential.that.the.corrective.actions.may.
actually.degrade.some.other.aspect.of.nuclear.safety..At.the.same.time,.the.impact.
that.corrective.actions.will.have.on.other.facilities.and.their.operations.must.be.con- sidered..The.proposed.corrective.actions.must.be.compatible.with.facility.commit-ments.and.other.obligations..In.addition,.those.affected.by.or.responsible.for.any.part.
of.the.corrective.actions,.including.management,.should.be.involved.in.the.process..
Proposed.corrective.actions.should.be.reviewed.to.ensure.that.the.above.criteria.have.
been.met,.and.should.be.prioritized.based.on.importance,.scheduled.(a.change.in.
priority.or.schedule.should.be.approved.by.management),.entered.into.a.commitment.
tracking.system,.and.implemented.in.a.timely.manner..A.complete.corrective.action.
program.should.be.based.not.only.on.specific.causes.of.occurrences,.but.also.on.items.
such.as.lessons.learned.from.other.facilities,.appraisals,.and.employee.suggestions.
A. successful. corrective. action. program. requires. that. management. be. involved.
at. the. appropriate. level,. be. willing. to. take. responsibility,. and. allocate. adequate.
resources.for.corrective.actions..Additional.specific.questions.and.considerations.in.
developing.and.implementing.corrective.actions.include
•. Do.the.corrective.actions.address.all.the.causes?
•. Will.the.corrective.actions.cause.detrimental.effects?
•. What.are.the.consequences.of.implementing.the.corrective.actions?
•. What.are.the.consequences.of.not.implementing.the.corrective.actions?
•. What.is.the.cost.of.implementing.the.corrective.actions.(capital.costs,.oper-ations,.and.maintenance.costs)?
•. Will.training.be.required.as.part.of.the.implementation?
•. In.what.time.frame.can.the.corrective.actions.reasonably.be.implemented?
•. What.resources.are.required.for.successful.development.of.the.correc-tive.actions?
•. What.resources.are.required.for.successful.implementation.and.continued.
effectiveness.of.the.corrective.actions?
•. What.impact.will.the.development.and.implementation.of.corrective.actions.
have.on.other.workgroups?
•. Is.the.implementation.of.corrective.actions.measurable?
PhAse Iv: InForm
Effectively.preventing.recurrences.requires.the.distribution.of.these.reports.(espe- cially.the.lessons.learned).to.all.personnel.who.might.benefit..Methods.and.pro-cedures. for. identifying. personnel. who. have. an. interest. are. essential. to. effective.
communications..Also.included.is.a.discussion.and.explanation.of.the.results.of.the.
analysis,.including.corrective.actions,.with.management.and.personnel.involved.in.
the.occurrence..In.addition,.consideration.should.be.given.to.providing.information.
of.interest.to.other.facilities..Finally,.an.internal.self-appraisal.report.identifying.
management. and. control. system. defects. should. be. presented. to. management. for.
more.serious.occurrences..Consideration.should.then.be.given.to.directly.sharing.
the. details. of. root. cause. information. with. similar. facilities. where. significant. or.
long-standing.problems.may.also.exist.
PhAse v: FolloW-uP
Follow-up.includes.determining.if.corrective.actions.have.been.effective.in.resolv-ing. problems.. First,. the. corrective. actions. should. be. tracked. to. ensure. that. they.
have.been.properly.implemented.and.are.functioning.as.intended..Second,.a.peri-odically.structured.review.of.the.corrective.action.tracking.system,.normal.process.
and.change.control.system,.and.occurrence.tracking.system.should.be.conducted.to.
ensure.that.past.corrective.actions.have.been.effectively.handled..The.recurrence.of.
the.same.or.similar.events.must.be.identified.and.analyzed..If.an.occurrence.recurs,.
the.original.occurrence.should.be.reevaluated.to.determine.why.corrective.actions.
were.not.effective..Also,.the.new.occurrence.should.be.investigated.using.change.
analysis..The.process.change.control.system.should.be.evaluated.to.determine.what.
improvements.are.needed.to.keep.up.with.changing.conditions..Early.indications.of.
deteriorating.conditions.can.be.obtained.from.tracking.and.trend.analyses.of.occur-rence.information.
summAry
Determining. facts. related. to. any. accident. is. the. key. to. an. accurate. and. effective.
analysis..Remember.to
•. Begin.defining.facts.early.in.the.collection.of.evidence.
•. Develop.an.accident.chronology.(e.g.,.events.and.causal.factors.chart).while.
collecting.evidence.
•. Set.aside.preconceived.notions.and.speculation.
•. Allow.discovery.of.facts.to.guide.the.investigative.process.
•. Consider.all.information.for.relevance.and.possible.causation.
•. Continually.review.facts.to.verify.accuracy.and.relevance.
•. Retain.all.information.gathered,.even.that.which.is.removed.from.the.acci-dent.chronology.
•. Establish.a.clear.description.of.the.accident.
Select.the.one.(most).direct.cause.and.the.root.(basic).cause.(the.one.for.which.
corrective. action. will. prevent. recurrence. and. have. the. greatest,. most. widespread.
effect)..In.cause.selection,.focus.on.programmatic.and.system.deficiencies.and.avoid.
simple.excuses.such.as.blaming.the.employee..Note.that.the.root.(basic).cause.must.
be. an. explanation. (the. why). of. the. direct. cause,. not. a. repeat. of. the. direct. cause..
In addition,.a.cause.description.is.not.just.a.repeat.of.the.category.code.description.;.
it is. a. description. specific. to. the. occurrence.. Also,. up. to. three. (contributing. or.
.indirect).causes.may.be.selected..Describe.the.corrective.actions.selected.to.prevent.
recurrence,.including.the.reason.why.they.were.selected,.and.how.they.will.prevent.
recurrence..Collect.additional.information.as.necessary.
reFerences
Chiu,. Chong..A. Comprehensive. Course. in. Root. Cause.Analysis. and. Corrective.Action. for.
Nuclear. Power. Plants. (Workshop. Manual).. San. Juan. Capistrano:. Failure. Prevention.
Inc.,.1988.
Gano,.D..L..Root.cause.and.how.to.find.it..Nuclear News,.August.1987.
Nertney,. R.J.,. J.. D.. Cornelison,. and. W.. A.. Trost.. Root. Cause. Analysis. of. Performance.
Indicators,.(WP-21)..System.Safety.Development.Center,.Idaho.Falls,.ID:.EG&G.Idaho,.
Inc.,.1989.
United.States.Department.of.Energy,.Office.of.Nuclear.Energy..Root.Cause.Analysis.Guidance.
Document..Washington,.D.C.:.U.S..Department.of.Energy,.February.1992.
United. States. Department. of. Energy.. Occurrence. Reporting. and. Processing. of. Operations.
Information,. (DOE. Order. 5000.3A).. Washington,. D.C.:. U.S.. Department. of. Energy,.
May.30,.1990.
United.States.Department.of.Energy..User’s.Manual,.Occurrence.Reporting.and.Processing.
System.(ORPS),.(Draft,.DOE/ID-10319)..Idaho.Falls,.ID:.EG&G.Idaho,.Inc.,.1991.
United. States. Department. of. Energy.. Accident/Incident. Investigation. Manual,. (SSDC 27,.
DOE/SSDC. 76-45/27),. 2nd. ed.. Washington,. D.C.:. U.S.. Department. of. Energy,.
November.1985.
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