ABSTRACT
French et al. (2011) have pointed out that current quantitative HRA approaches in general lack the precision for use in the summative way that system designers, managers and regulators often utilize them. In this context ‘summative’ refers to viewing the quantitative end result as the goal of the HRA process. Rather, they recommend that HRA approaches should be used in a formative way where the insight gained from the process is the main goal, and the quantitative end result is taken with “a pinch of salt”. However, when many textbooks on risk analysis address the usage of HRA methods, the suggested approaches seem to be mainly summative in that plugging in HEPs is the goal of the process; see for example Rausand (2011), Ostrom and Wilhelmsen (2012) and Flaus (2013). We see the need for a method that fits with this traditional way of using HEPs, as these serve a purpose in the QRA, but one in which the HRA is used more formatively in the assessment of risk. To achieve such a method, we apply a broader framework of risk assessment than the more traditional probability based risk assessment frameworks.
