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The University of Southampton
Southampton Business School

How safe is safe enough? - the answer provided by the J-value Seminar

15:00 - 16:00
13 November 2019
Building 2, Room 3043, Highfield campus, University of Southampton, SO17 1BJ

Event details

Business School seminar

There is an entirely justified desire to improve the health and the safety of the nation's citizens.  Until recently, however, there has been a lack of quantitative guidance on how much ought to be spent on a health and safety measure.  But now the J-value can provide an objective and empirically validated answer to the vexed question: "How safe is safe enough?".

The lecture will start by clarifying what it is we mean by "saving a life" and go on to explain why life expectancy is a key variable in the new science of safety.  The concepts of the Life Quality Index and the J-value will then be introduced and explained.  It will be shown how the J-value can be used to advise when sufficient safety has been attained.

Three separate validations will be presented for the J-value. 

Previous applications of the J-value will be illustrated.  Particular attention will be given to the J-value evaluation of the measures adopted after the Fukushima Daiichi nuclear accident, where the cores of 3 large nuclear reactors melted down following inundation by a severe tsunami, leading to large releases of radionuclides and the widespread deposition of nuclear fallout around the surrounding areas.

Speaker Biography:

Philip Thomas, Professor of Risk Management, University of Bristol


Philip Thomas, Professor of Risk Management,
Philip Thomas, Professor of Risk Management,

Philip Thomas researches risk management, where he has developed the J-value, a method that enables objective decisions to be taken on safety expenditure.  His team recently presented the results of the NREFS project on coping with a big nuclear accident to the All-Party Parliamentary Group on Nuclear Energy.  The closing papers of that study formed a Special Issue of Process Safety and Environmental Protection, generating over 35,000 downloads since publication in November 2017.  His work on risk has been covered by both written and broadcast media.  The PSEP Special Issue was reported by The Times and other papers before "going viral" on internet news outlets.  The research was cited extensively by the Financial Times on the 7th anniversary of the Fukushima Daiichi accident.

Professor Thomas graduated in Cybernetics and Instrument Physics from Reading University with a BSc (First Class Honours) and University Prize.  City, University of London awarded him a DSc in 2005 for his contribution to science and engineering.  He gained over 20 years' experience in the chemical and nuclear industries, first at ICI plc developing control systems for large chemical plants then with the UK Atomic Energy Authority. Here he headed up Departments concerned with: C&I product development, non-destructive testing technology and materials research, and research into remote handling and decommissioning of nuclear plant.  He was Customer Project Manager for the green-field decommissioning of the 100MWth/33MWe Windscale AGR.  City, University of London appointed him Professor of Engineering Development in 2000 and he moved to the University of Bristol to take up a Chair in Risk Management in 2015.  His research has received sponsorship from the UK Research Councils, Government departments, the EU and industrial companies. 

He has published over 120 journal and conference papers on control, instrumentation, nuclear decommissioning, risk assessment, economics and law.  His book, Simulation of Industrial Processes for Control Engineers, was published in 1999.  The Institute awarded him its ICI Prize in 1984, 1987 and 1997 and its Honeywell International Medal in 2004.  The Worshipful Company of Scientific Instrument Makers presented him with its Best Paper Prize, 2006, for his article introducing the J-value.  The IChemE awarded him "Most Cited Author" certificates for each of the first three J-value papers in 2009, while Elsevier presented him with "Top Cited Paper" certificates for two further J-value articles.  His paper on measuring risk-aversion is currently (2019) cited by IMEKO's Measurement journal as its most downloaded article.

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