1Why model before analysing
Before listing hazards or failure modes, first establish what is being analysed: which system, function and component. Facility modelling creates this structure once so that every subsequent method—PHA, FMEA, HAZOP and BowTie—uses it consistently. A component is identified once rather than redefined differently in every table.
Page to be completed — system/function/component/variable hierarchy, example breakdown and granularity best practices.