“A fault tree for a refinery storage-tank vapor cloud explosion: flammable release, ignition and congestion must all occur. Release is tank rupture, piping leak, valve leak or overfill. Ignition is electrical spark, hot work, static discharge, mechanical spark or lightning.”
Read the decisions behind it.
Modeled release as OR of tank rupture, piping leak, valve failure, and overfill
electrical, hot work, static, mechanical sparks, lightning
Added congestion/confinement as a prerequisite with high probability (0.9)
Used flat declaration with explicit gate wiring for clarity and reusability of basic events
When performing quantitative risk assessment for flammable vapor cloud explosions in petrochemical storage areas; easily adaptable to other release and ignition scenarios by adding/removing basic events.