Risk assessment of machinery supported by the Bayesian approach

Meeting safety requirements and conducting a conformity assessment is an obligatory process for machinery developers and manufacturers in the European Economic Area. Risk assessment of machines within the framework of the conformity assessment procedure is performed based on the harmonized standard ISO 12100 and the technical report ISO/TR 14121-2. These documents offer a basic description of approaches for machinery risk assessment. The ISO 12100 standard provides machinery designers and manufacturers with information for ma chinery to comply with essential requirements stated in Directive 2006/42/EC on ma chinery. With the development of digital technologies and the introduction of the new Machinery Regulation (EU) 2023/1230, the need to consider the requirements of the EN ISO 13849 control system safety standard and the EN IEC 62061 Safety Integrity Levels (SIL) standard has emerged. However, making decisions about the risks of machinery as a complex system is not an easy task. The ISO 31000 risk management standard recommends applying the theory of probability for uncertainty consideration when assessing risks. Bayesian analysis is one of the methods for applying a probabilistic approach and considering uncertainties to support decision-making when assessing machine safety risks.