Ilizastigui, P.F.; Ilizastigui, A.I.
[email protected]
IAEA – CN-236/05
IAEA-IEM 9-15
National Centre for Nuclear Safety
INTRODUCTION
Historically, the majority of nuclear safety reports have been produced and applied under prescriptive legislative regimes, with emphasis placed on demonstrations of the robustness of
the facility’s design against technical standards and rules set by the Regulatory Body. As a result, they are often “inaccessible” to key “users” (those who actually exercise direct control
of the hazards and risks at the plant as well as the managers who hold specific accountabilities and responsibilities for ensuring safe facility’s operation). This situation has a detrimental
effect on the safety of the facility particularly during operations, when the Safety Report is intended to be actively used by those key users as an effective tool to support informed
decision making in relation to the day-to-day management of operational risks. This paper explores the strengths of the Bowtie risk management methodology in producing fit-forpurpose, accessible and usable Safety Reports that will support current efforts undertaken by the nuclear industry to ensure “Right First Time Safety Cases”.
SAFETY REPORT PRODUCTION PROCESS
“I am concerned that the
exponential growth of ‘the
Safety Case industry’ has led
to a culture of ‘paper safety’ at
the expense of real safety”
UK Nuclear Safety Case Forum
C. Haddon-Cave
● Selection of accident
scenarios for risk reduction
with Bowtie
● Facilitation of Bowtie Workshops
with facility personnel
● Barrier Effectiveness rating
● Assignment of responsibilities for
barriers
● Identification of Safety Critical Tasks
(SCTs)
Bowtie ALARP
Workshop
● Preparation of “Draft” Bowties
● ALARP definition
(Qualitative)
● Conduction of
Bowtie/ALARP Workshops
● Compilation of Plan of
Remedial Actions
Management of Safety
Critical Systems (SCS)
● Identification of
potential accident
scenarios
● Estimation of risk of
accident scenarios
Bowtie Review
Workshop
● Check HAZID for
completeness
Risk Estimation
HAZID
BOWTIE IMPLEMENTATION ROADMAP
● Register of SCSs from the final Bowtie
diagrams
● Review of SCS adequacy
● Confirmation of SCTs
● Development of Performance Standards
● Development of Summary of Operational
Boundaries (SOOB) Matrices
● Development of Key Performance
Indicators
RESULTS
CONCLUSIONS
• The implementation steps described in the paper can serve as a practical “roadmap” for the production of safety reports that can be “actively embraced” by the
non-nuclear sectors, particularly by the emerging technologies in the industrial and medical sectors. These modern technologies “deserve” modern safety
reports that incorporate state-of-the-art risk management methodologies that not only ensure compliance with existing regulatory requirements but produce
usable, accessible and easy-to-understand and update Safety Reports. This will undoubtedly have a major effect in the reduction of risks from radiation sources
used in those industries.
• So far, the IAEA Safety Case concept has successfully integrated the safety assessment with the Safety Report. The next logical step would be to integrate the
safety assessment with the safety management system and make this integration “visible” within the Safety Report. This will significantly contribute to the
demonstration that the existing safety management is indeed effective in supporting engineering controls upon which the safety of the facility is based. The
Bowtie methodology will be the advisable option to show the manner in which safety critical tasks forming part of SMS ensure the ongoing integrity of those
engineering controls and monitor their performance.