Nuclear Power Plant Safety

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Nuclear power plant safety:Steps toward better performance

At many nuclear plants, self-assessment processes are helpingmanagement to review and improve levels of safety

by Keith Hide r\s part of the nuclear industry's response to

the accidents at Three Mile Island (TMI) in 1979

and at Chernobyl in 1986, programmes to evalu-ate and encourage improvements in the opera-tional safety performance of nuclear powerplants were initiated. In the United States, theInstitute of Nuclear Power Operations (INPO)was founded by nuclear utilities. It performs pe-riodic operational safety evaluations of all nu-clear power plants in the USA. INPO also pro-vides a number of other services to help US andvolunteer international utilities improve theirsafety performance.

On a broader international scale, the IAEAinitiated the Operational Safety Review Team

(OSART) programme for voluntary reviews ofoperational safety performance at power plantsworldwide. The IAEA also initiated other volun-tary programmes — such as those on the Assess-ment of Safety Significant Events (ASSET), As-sessment of Safety Culture in Organizations(ASCOT), and the Incident Reporting System(IRS) — to assist nuclear plant operators inevaluating and strengthening their safety per-formance.

In September 1994, IAEA Member Statesbegan the process of ratifying a new Convention

on Nuclear Safety. This convention will estab-lish, for the first time, internationally agreed ob-ligations for ensuring the safety of nuclear pow erplants and the commitment of the signatoryStates to meeting them. Under the Convention,Member States with nuclear power plants willreport periodically to their peers on the measurestaken to meet their obligations.

Although the exact nature of the reports to bemade under the Convention has yet to be deter-mined, Member States will need to determine, in

Mr. Hide is Head of the Operational Safety Section of the IAEA

Division of Nuclear Installation Safety.

some way, the degree to which the performanceof their own nuclear power plant programme is

in accordance with the obligations of the Con-vention. Operational safety performance reviewsperformed by independent organizations such asthe IAEA could provide information for this pur-pose, but the substantial outside resources theyrequire limit their availability.

Many utilities have chosen to use self-assess-ment processes to help their management obtaincurrent information about safety performance.Regulatory authorities are increasingly recognizingand using self-assessments to judge nuclear powerplant safety performance. Experience has shownthat when organizations objectively assess their

own performance, understanding of the need forimprovements and the motivation to achieve themis significantly enhanced. Such self-assessmentsmight also contribute substantially to the periodicreports required by the Convention.

For purposes of discussion, self-assessmentpractices can be grouped into three general areasas follows:

• frequent or continuou s mon itoring of per-formance against established managementperformance expectations;

• periodic, in-depth reviews of the effective-

ness of selected activities or programmes byin-house teams of experienced reviewers andtechnical experts; and

• one-tim e, in-depth reviews to probe the fullextent and basic causes of known weak per-formance areas.

This article outlines these self-assessmentpractices and the benefits they are providing.

Performance monitoring

Many utilities now use a variety of perform-

ance indicators to set and communicate theirgoals or expectations for performance of plant

equipment, programmes, and personnel in areas

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that affect safety, production and efficiency. Per-formance indicators are best expressed in clear,numerical terms that relate to performance in avariety of areas. They normally include the tenmajor performance indicators that are reported tothe World Association of Nuclear Operators(WANO) by nuclear utilities worldwide and asubstantial num ber of others that are based on theparticular needs of individual plants and groups,such as chemistry, radiological protection, andmaintenance, within plant organizations. Manyplants use the results achieved by top-performingplants or established industry standards asbenchmarks to set their own goals for perform-ance and improvement.

Structured monitoring of actual performanceresults against the agreed performance indicatorgoals helps provide management and other plant

personnel w ith useful information on the currentperformance and areas in need of additional at-tention. Some utilities establish, for each per-formance indicator or related groups of indica-tors, a series of numerical values that reflectsignificant weakness, the need for some im-provement, satisfactory performance, or signifi-cant strength. Periodic reports to managem ent onperformance can then be tailored to reflect notonly the current level of performance, but thetrend in performance. Colour-coding is some-times used to help highlight results and trends inthese reports.

Performance monitoring against goals pro-vides management with frequent, objective in-formation on the quality of plant operations inthe areas addressed by the performance indica-tors. It further allows managers to address theirattention to the areas where assistance or addi-tional support may be needed to meet stationperformance goals. Another major advantage ofthis type of monitoring is that reports of perform-ance can be easily shared, by means of graphsand visual presentations, with all plant person-nel. This helps keep all personnel aware of cur-

rent performance in their own areas and in areasthat they support. Some utilities format thesereports in the form of annunciator panels colour-coded to reflect the results according to specifiedperformance categories, and display themthroughout the plant. Many have found that theuse of such systems significantly enhances un-derstanding and support within the plant staff ofmanagement's goals for performance and howthey relate to their own activities.

Periodic effectiveness reviews

Though performance indicators and goalsprovide information on a frequent basis, their

value is limited to the specific areas selected formonitoring, and they do not give much insightinto the causes of performance weaknesses. Ef-fectiveness reviews that look into qualitative aswell as quantitative information have alsoproven to be valuable self-assessment tools.These reviews do examine adherence to regula-tory or external requirem ents, but the most effec-tive reviews go well beyond that to examine the

effectiveness and efficiency of programmes andactivities in achieving their intended purpose.Effectiveness reviews of major plant evolutions,such as outages and plant startups, often providevaluable insights into plant and staff perform-ance. They may also be useful in assessing theeffectiveness of corporate support or supportfrom other organizations that can impact plantoperation and safety performance.

Effectiveness reviews may be accomplishedby teams of individuals who are independent ofthe activity being reviewed, by those who are

closely involved in the activity on a day-to-daybasis or, ideally, by teams including both. Suchreviews may be done well by quality assurancepersonnel, if they have current expertise and expe-

Members of an OSART

team at the Hamoaka

nuclear plant in Japan.

(Credit: Taylor/IAEA)

IAEA BULLETIN, 4/1995



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rience in the area to be reviewed. However, manyutilities have discovered the advantages of usingpersonnel who are directly involved in or respon-sible for the activity under review as members of

these teams. Such individuals bring valuable in-

sights into the review process and improve the

quality of review results. But perhaps more im-portantly, they often gain fresh perspectives and

understanding from their participation that in-

creases their awareness of problems, the impor-tance of correcting them and possible ways of

correcting them. In addition, the training theyreceive in review techniques by virtue of theirparticipation often significantly improves theirability to assess performance in their own areasof responsibility on a day-to-day basis.

Strong support from management has beenshown to be an essential factor inachieving good

effectiveness reviews. Thiscan be

shownby se-

lection of capable review team members includ-ing appropriate management and supervisorypersonnel, support of each team's efforts to iden-tify all contributing problems and their causes,and responding to the results of reviews in a

positive way that supports improvement withoutpunitive action or embarrassment. These factorsare important to obtaining the open sharing of

information and opinion between reviewers and

those being reviewed that is needed to producegood results.

Quality assurance programmes have tradi-

tionally provided a framework for review oraudit of station programmes and activities, usingreview schedules that provide periodic examina-tion of important performance areas and focus-ing on adherence with quality programme re-

quirements andregulations. However, many cur-

rent self-assessment efforts expand considerablyon this framework by performing reviews at the

request of managers or staff personn el and focus-ing more onoverall effectiveness of programmesand activities in achieving their intended pur-

pose. In some plants, more than 50% of theassess-ments performed are a consequence of plant staff

requests, and managers and other personnel at all

levels participate inassessment team s.

One-time reviews of problem areas

Most utilities recognize that focusing self-as-sessments or effectiveness reviews on known or

suspected problem areas is one of the most effec-tive ways of improving performance. At leastone utility senior manager has stated that his

manager's primary responsibility is finding

problems and opportunities for improvement andmaking theappropriate improvements. Opportu-nities for improvement may be identified

through performance indicator monitoring, plantand industry operating experience, comparisonwith other nuclear power plants, and a variety of

other means. The principles for achieving goodreviews are the same as those stated above for

periodic reviews.

An example of the use of one-time problemreviews concerns the system used at one nuclearpower plant to tag equipment that was out-of-

service for maintenance work. After a few minorcases of errors in tagging, plant managers de-

cided to conduct an in-depth review of its tag-

ging procedures and related activities. Theyformed a team that included members of the

maintenance staff, operations staff, technicalsupport staff, and others, and required them to

examine all aspects of the tagging system. The

team attempted to flow-chart thetagging processand found that they were unable to do so. At the

conclusion of their work, the team had identifiedmany deficiencies in the effectiveness of the sys-

tem, foremost of which were its complexity and

the lack of understanding of it by those whousedit on a day-to-day basis. The plant then devel-oped a completely new, simpler process thatcould be more easily understood and used morereliably.

In another example, a utility that had experi-enced several indications of deteriorating per-

formance in broad areas elected to perform a

comprehensive review of the management and

effectiveness of all station activities. In this case,the problems were considered to be so pervasivethat the utility decided the team should be com-

prised of experienced plant operations expertsfrom outside the company. A team of seniorexperts with excellent knowledge and currentexperience in plant operations and managementwas assembled by the utility and given strongsupport in identifying the fundamental causes of

the plant's malaise. The results initiated manyfundamental improvements in the managementof plant activities and the responsibilities givento plant personnel. It was recognized by the na-

tional regulatory authority as an effective identi-fication of fundamental problems at theplant. As

a result, an extensive regulatory review was

avoided. Both the regulatory authority and the

plant considered the self-assessment more usefulthan a regulatory inspection, because of the ex-

pertise of the reviewers and because of the plant'spositive recognition and ownership of the results.

Peer review programmes

Utilities in at least four countries have imple-mented their own peer review programmes and

are using their own expertise to assess perform-

10 IAEA BULLETIN, 4/1995



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ance in each of their nuclear power plants. Theyhave organized programmes for peers from otherstations to assess each of their nuclear stations atregular intervals. These programmes providevaluable training in proven review techniques to

numerous plant personnel who participate aspeer reviewers. The knowledge and experiencethey gain pay dividends when they return to theirown plants. They can view performance in theirown areas more objectively and with a freshperspective. Often, they get ideas from the plantbeing reviewed that they use to strengthen theirown performance.

Regulatory overview

Some regulatory agencies believe that en-

couraging self-assessment and checking on thethoroughness and results of such efforts providesvaluable insight for the regulator and promotes asense of ownership for problem identificationand correction within the utility, where it is mostimportant. As a result, they are increasing theirefforts to ensure that all utilities implement ef-fective self-assessment programmes to detect op-erational weaknesses and identify the fundamen-tal causes early. It is believed that review ofself-assessment results can be an improved alter-native to regulatory inspections as a means of

ensuring that plants maintain high standards ofperformance.

International initiatives

Those involved in the use of self-assessmentprogrammes agree that self-assessments repre-sent one of the most powerful tools for improve-ment because of the following benefits:

• They are performed by individuals who aremost knowledgeable of the people and prac-tices at the nuclear power plant.

• They can be easily tailored to the needs ofindividual plants.

• They minim ize the potential for emba rrassingexposure of plant weaknesses to outside per-sons, and maximize the opportunity for can-did, frank discussion of problem areas be-tween reviewers and staff members.

• They strengthen insight into performanceproblems, their causes, and their effects at alllevels, and thus strengthen support for im-provement.

• They can be performed on a frequent or con-tinuous basis, giving management current in-formation on the effectiveness of a wide vari-ety of programmes and activities.

The IAEA is considering how it might bestsupport the development and use of self-assess-ments as a means of strengthening nuclear powerplant operational safety. Activities in progress orunder consideration include the following:

• providing guidance on self-assessment activi-ties for utilities and regulators. An IAEASafety Guide is being developed;

• supplem enting the OSAR T process andOSART guidelines (IAEA TECDOC-744,May 1994) to provide for reviewing the effec-tiveness of plant self-assessment activities;

• using the OSA RT process to identify and col-lect best practices in self-assessment and shar-ing them with the industry through theOSART Mission Results data base (OSMIR)and other methods;

• sponsoring international conferences andworkshops on self-assessment;

• assisting Member States in implem entingself-assessment programmes, upon request;

• reviewing self-assessment processes and theresults of self-assessments upon request.Expectations for operational safety perform-

ance are reaching higher and higher levels, andinternational interest in the performance of indi-vidual nuclear utilities and power plants is in-creasing. In this climate, the use of effectiveself-assessment processes is expected to become

more important in both well-developed and de-veloping nuclear programmes. Frequent, criticalself-examinations of safety performance will berequired to ensure that acceptable levels of per-formance are achieved and maintained. As partof its safety serv ices to Mem ber States , the IAEAwill do its best to support and encourage the useof self-assessments in nuclear utilities and powerplants. •

Leibstadt nuclear plant,

Switzerland.

IAEA B ULLETIN, 4/1995 11

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Nuclear Power Plant Safety