Study execution
How the study is executed
A structured, facilitated process — from scope definition through close-out — producing defensible, actionable outputs.
Building Inventory & Occupancy Classification
Compile building register per API RP 752 (permanent), 753 (portable), 756 (tents); record structural type (brick, portal frame, modular, BRM), occupancy (peak persons, occupied hours, staff vs contractor), and building GPS coordinates; flag building modifications since last OBRA cycle.
Explosion Source Term & Overpressure Modelling
Link explosion scenarios from FERA or CDM study to building locations; apply Multi-Energy / Baker-Strehlow-Tang for standard cases and FLACS / KFX CFD for high-confidence VCE cases; calculate side-on overpressure, positive phase duration, and impulse at each building façade.
Building Damage Assessment
Apply ASCE Petrochemical Energy Committee structural fragility curves per building type; derive probability of minor / moderate / major damage / collapse; calculate personnel fatality and injury probability per blast damage state using Pietersen / Stephens injury probit functions.
Thermal Radiation & Toxic Infiltration Assessment
Calculate thermal dose and skin-burn / structural ignition risk at each building from fire scenarios; model toxic infiltration via HVAC air-change rate and infiltration factor against AEGL-2 / SLOT criteria; determine shelter-in-place viability and maximum safe duration.
Risk Metrics — IRPA, PLL, F-N Aggregation
Calculate Individual Risk per Annum (IRPA) per building; compute PLL weighted by occupancy; where multi-building aggregation required, produce F-N curves; compare against API RP 752 tolerability criterion; identify buildings exceeding threshold requiring priority action.
Retrofit Recommendations & Occupancy Management Plan
Develop building-by-building upgrade options (BRM procurement, structural reinforcement, relocation, demolition, occupancy reduction) with blast-load specification; produce cost-benefit appraisal; issue occupancy management plan for turnarounds and routine operations; specify 5-year re-assessment trigger matrix.
