IEC 62502:2010 specifies the consolidated basic principles of Event Tree Analysis (ETA) and provides guidance on modelling the consequences of an initiating event as well as analysing these consequences qualitatively and quantitatively in the context of dependability and risk related measures.
GSO IEC 62502:2013 history
2013GSO IEC 62502:2013 Analysis techniques for dependability - Event tree analysis (ETA)