Developing leading safety indicators for occupational safety based on the bow-tie method

In order to control occupational accidents, it is crucial to have a clear view on the potential accident scenarios that are present in a company. The bow-tie method is a way to capture and visualise these accident processes in an integrative way. Included in the bow-tie are safety barriers (both technical as organisational and human) and management delivery systems that can intervene in these accident processes. Once bow-ties are composed, they are an excellent point of departure to assign indicators to the safety barriers and management delivery systems in order to control (i.e. prevent or mitigate) the accident scenarios. Two types of indicators can be distinguished. Firstly, there are general indicators that are linked to management delivery systems interrupting multiple accident scenarios, and which can yield a higher safety gain (as they intervene in multiple accident scenarios). Secondly, there are scenario-specific indicators targeting one specific accident scenario, and which can be valuable as they target a specific safety problem in the company. Some crucial aspects have to be taken into account when using indicators, such as sequentiality in follow-up and prioritization of indicators, and the focus on quality rather than quantity.