Seminar on The Reactor
Safety Analysis: Deterministic versus Probabilistic
Organizer: HKIE-Nuclear Division
Supporting Organizer: City University of Hong Kong,
Department of Mechanical and Biomedical Engineering, & Hong Kong Nuclear
Society
Date, Time and
Venue
10 April 2018 (Tuesday); 6:30 p.m.; Room 1511, 1/F, Li Dak Sum
Yip Yio Chin Academic Building, City University of Hong Kong, Kowloon Tong,
Hong Kong
Programme
Highlights
In the reactor safety analysis, both deterministic and probabilistic
methods are used. In this seminar, both methods currently used in the nuclear
industry will be introduced and discussed. Firstly, the deterministic method
with the nine categories of design basis nuclear accidents analyzed in the
Final Safety Analysis Report (FSAR) will be introduced. After that, the
probabilistic risk assessment (PRA) will be addressed together with the
introduction on WASH-1400, the pioneering safety analysis report using PRA.
Finally, some CityU researches on severe accidents will be presented.
Speaker
Dr. Zhao JiYun is currently an associate professor in
Nuclear and Risk Engineering Program at City University of Hong Kong and a
member of American Nuclear Society.
Registration
and Enquiries
The seminar is free of charge and prior registration
is required. The number of participants will be limited to 80 and applicants
will be accepted on a first-come-first-served basis. Priority will be given to
the members of Nuclear Division. For registration, please complete and return
the Standard Reply Form to Ms Annie KOU via Email: nuclear@ne.hkie.org.hk by 6 April 2018 Successful applicants will be notified by emails. For
enquiries, please contact Ms Annie KOU at nuclear@ne.hkie.org.hk.
Disclaimer
All information and views expressed by speakers and in
their conference materials do not reflect the official opinion and position of
HKIE. No responsibility is accepted by the HKIE or their publisher for such
information and views including their accuracy, correctness and veracity.
Report
Seminar on "Reactor Safety
Analysis: Deterministic versus
Probabilistic”
Prepared by Mr Paul Y H Wang
A technical seminar was organized by the Nuclear
Division on “Reactor Safety Analysis: Deterministic versus Probabilistic” on 10 April 2018 at the City University of Hong Kong. The
seminar was presented to around 30 participants by Dr. Zhao JiYun, Associate Professor in Nuclear and
Risk Engineering program at the university.
While reactors
may differ greatly in design and detailed engineering characteristics, they
share certain basic design safety principles, including the multiple-barrier
concept for fission-product containment and its related defense-in-depth. The
defense-in-depth philosophy mandates safety systems that are independent,
diverse, and redundant. However, this philosophy does not identify the level of
redundancy needed. To make these decisions, both deterministic and
probabilistic methods are used in the reactor safety analysis. The Deterministic
Risk Assessment (DRA) uses postulated accidents and the single failure
criterion. In contrast, the Probabilistic Risk Assessment (PRA) take a holistic
approach which evaluates risks associated with every life-cycle aspect of a engineering
entity from concept definition, through design, construction and operation, and
up to decommissioning.
As a
probabilistic safety goal, the US Nuclear Regulatory Commission (NRC) issued
the Quantitative Health Objectives (QHO) specifying the risk from a nuclear
power plant to be less than 1/1000th of the total risk for those living near
the plant. The pioneering report WASH-1400 in 1975 that assessed accident risk
of US commercial nuclear power plants was the first attempt to provide a
realistic and systematic assessment of their risks. Despite subsequent
refinements, the basic probabilistic risk assessment (PRA) approach promulgated
in WASH-1400 is still relevant today. Dr. Zhao JiYun also went to some lengths to illustrate current nuclear research at the university.
In
conclusion, the seminar was very fruitful and of special interest to the
members for an insight into the Reactor Safety Analysis. On behalf of the Nuclear
Division, we wish to express our sincere gratitude to Dr. Zhao JiYun for providing
this informative seminar to our members.
Photo
caption: Dr. Zhao JiYun (right) receiving a souvenir from Ir Ryan Lam, Deputy
Chairman of the Nuclear Division