Quality of Risk Assessment: Definition and Verification

International audienceThis chapter focuses on the risk assessment goal of describing and characterizing knowledge and lack of knowledge. It reflects current thinking about risk, which shows a trend towards seeing uncertainty as a key element of risk, see for example the ISO 31000 definition of risk, the definition of risk by the Petroleum Safety Authority (PSA‐N 2015) and the recommendation given by the new Society for Risk Analysis Glossary (SRA 2015). In line with such risk conceptualisations, more focus is placed on knowledge and lack of knowledge descriptions and characterisations, compared to more traditional probability‐based perspectives. The chapter addresses the difference between risk as characterised by analysts and the risk to be considered by decision makers. The point made is that decision makers need to address unconditional risk and not only conditional risk as described by the risk analysts and experts