International Atomic Energy Agency
Regional Technical Meeting on Harmonizing Safety Assessments and
Creating Synergy between Deterministic and Probabilistic Safety Analyses
PROSPECTUS
Project Number
& Title:
TC PROJECT RER/9/126
Place (City,
Country):
Dubrovnik, Croatia
Dates:
Deadline for
Nominations:
26 - 30 March2012
Organizers:
The International Atomic Energy Agency (IAEA) in collaboration with the
Government of Croatia through the University of Zagreb
Host Country
Organizer:
Prof. Dr. Nikola Cavlina
University of Zagreb
Faculty of Electrical Engineering and Computing (FER)
Unska Ulica 3
10000 Zagreb
Croatia
Tel: 00385 1 6129907
Fax: 00385 1 6129890
E-mail: nikola.cavlina@fer.hr
Language:
Purpose:
The meeting will be conducted in English.
The purpose of the meeting is to address the synergy between Deterministic
and Probabilistic Safety Analyses.
Historically, the guiding principles for design and operation of Nuclear
Power Plants (NPPs) were deterministic requirements. The main elements
were defence-in-depth provisions, safety margins, compliance with the
single failure criterion, and some other. The Probabilistic safety
Assessment (PSA) method has evolved later on and in difference to the
deterministic approach, it had an aim to give answers to what can go
wrong, how likely is it to happen and what are the consequences.
In recent years a lot of effort has been devoted towards the harmonization
of both types of analysis – deterministic and probabilistic and in
establishment of their relative roles. In particular, the way that the insights
from the two analyses can be obtained and combined in making decisions
on nuclear safety issues, and the relationship between the deterministic and
probabilistic analysis in addressing high level requirements such as defence
in depth and safety margins.
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In this context it is essential to determine how can deterministic safety
analysis be improved to provide better support for the probabilistic safety
analysis. On the other hand, it is as important to determine how can the
PSA results be better used to investigate the provisions for defence in depth
and for evaluation of safety margins.
Expected
Output(s):
Knowledge shared among participants on the subject of the meeting. The
final state-of-the-art meeting report will provide summary of presentations,
deliberations and conclusions from the meeting.
Scope and
Nature:
The technical meeting will consist of presentations and discussions in
working groups. All participating countries are expected to present their
national experience/approach related to the subject of the meeting
The overall objective of this project is to enhance and maintain high levels of
nuclear safety in Member States by strengthening their capabilities for
performing safety assessments of their Nuclear Power Plants.
This technical meeting will contribute towards this objective by providing and
exchanging information on specific aspects as outlined above under the
“Purpose of the meeting”.
Background
Information:
Participation:
The meeting is open to 20 participants.
The target countries are: [Pavel, please check the list of countries}Armenia,
Belarus, Bulgaria, Croatia, Czech Republic, Hungary, Kazakhstan, Lithuania,
Poland, Republic of Moldova, Montenegro, Romania, Russian Federation,
Serbia, Slovakia, Slovenia, Republic of Tajikistan, Turkey, Ukraine and
Uzbekistan.
Participants’
Qualifications:
The participants should be professional staff members of the regulatory
authorities, utilities and design or technical support organizations from the
region.
Nomination
Procedure:
Nominations should be submitted on the standard IAEA Nomination Form
for Meeting/Workshop and National Consultant (available on the IAEA
website: http://www.iaea.org/). Completed forms should be endorsed by
relevant national authorities and returned to the Agency through the official
channels, i.e. the designated National Liaison Office for IAEA Matters.
The completed nomination forms should be sent to the Programme
Management Officer for this project, [Name of PMO], through IAEA
Official Fax (+43-1-26007) or E-Mail (Official.Mail@iaea.org), not later
than [Date]. Nominations received after this date or which have not been
routed through the established official channels cannot be considered.
Administrative
and Financial
Arrangements:
Nominating Governments will be informed in due course of the names of the
candidates who have been selected and will, at that time, be given full details
of the procedures to be followed with regard to administrative and financial
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matters.
Selected participants from countries eligible to receive technical assistance will
be provided with a round trip economy class air ticket from their home
countries to Dubrovnik, Croatia, and a Daily Subsistence Allowance (DSA) at
the prevailing UN Rate. Shipment of accumulated meeting materials to the
participants' home countries is not the responsibility of the IAEA.
The organizers of the meeting do not accept liability for the payment of any
cost or compensation that may arise from damage to or loss of personal
property, or from illness, injury, disability or death of a participant while he/she
is travelling to and from or attending the meeting, and it is clearly understood
that each Government, in nominating participants, undertakes responsibility for
such coverage. Governments would be well advised to take out insurance
against these risks.
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IAEA - TC Regional Technical Meeting on
“Harmonizing Safety Assessments and Creating Synergy between Deterministic and
Probabilistic Safety Analysis”
RER/9/126
Dubrovnik, Croatia
26 – 30 March 2012
SYLLABUS
1.
Introduction
Overview of the Technical Meeting
Technical Meeting objectives
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Deterministic safety analysis in support of PSA
 Determination of the set of initiating events,
 Analysis of success criteria for safety systems and accident progression following an
initiating event,
 Analysis for internal and external hazards,
 Severe accident phenomena, containment performance and source term calculations
for level 2 PSA.
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Insights from the deterministic analysis:
 High level requirements that relate to
o defence in depth
o adequate safety margins
 Lower level requirements for the safety systems
o redundancy
o diversity
o separation/segregation
o fail safe actuation
o equipment qualification
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Insights from the PSA:
 Quantitative risk measures and criteria for decision making:
o core damage frequency (CDF)
o large early release frequency(LERF)
o importance measures
o reliability of safety systems/functions
o quantitative safety goals
 Consideration of uncertainties:
o sensitivity analyses
o uncertainty analyses.
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Relationship between the deterministic analysis and the PSA in
addressing
defence in depth:
 How the results of the PSA can be used to investigate the provision of defence in
depth, and
 How the PSA could be structured to make this comparison easier.


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Relationship between the deterministic analysis and the PSA in
addressing
safety margins:
 How the design basis analysis and the PSA compliment one another
 How the relationship between the design basis analysis and the PSA could be
improved - for example, by using a probabilistic approach for defining design basis
accidents, and
 What analysis needs to be carried out for beyond design basis fault conditions to
determine whether they need to be included in the PSA.
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Approaches and examples of integration of deterministic and probabilistic
analysis in safety related decisions, addressing:
 The preservation of defence in depth and sufficient safety margins
 How the weights from the deterministic and the probabilistic analyses, and other
factors can be combined in making decisions on safety issues, such as applications to
backfitting and development of new reactor designs.
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National Presentations
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