Risk validation by the regulator in Seveso companies: Assessing the unknown

This longitudinal case study centres around a ‘narrative’ compiling 13 years of regulatory experience with risk assessment in practice of major hazard control of Dutch Seveso companies. The narrative is written by the first author, retired as an inspector mid-2016. The concept ‘narrative’ was reviewed, debated and methodically interpreted by the second author. The narrative story considers risk assessment as the current basis for successful prevention and sound safety management, in line with current thinking. An inventory of risks for society, workers and environment, originating from a company that is eligible to receive a licence to operate, is essential for the regulator's decision-making. It needs to cover all risks since acceptance of incomplete assessments imply implicitly accepted, yet uncontrolled, danger. Risk inventories in practice tend to be elaborate yet incomplete. Shortcomings identified via assessment by the regulator, are mainly found in the areas of known but ignored danger, lacking evidence for chance and effect, lacking underpinning of the completeness of the inventory and lacking checks whether as yet unknown danger of various types could be threatening safety. This study has three results: an exploration of current thinking about risk based regulatory approach as described in literature, an experts' narrative on pitfalls in regulatory practice and an analysis leading to new insights about incomplete risk assessments. Conclusion is that progressing towards validation of company risk assessments by the regulator would require more uniformity of company risk assessments, a standard regulator appraisal method and, as an additional safeguard, a systematically performed completeness check.