Consequence Modeling

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Consequence Analysis—also known as Consequence Modeling—is performed to quantify the potential effects of Loss of Containment (LOC) scenarios in industrial facilities. This analysis involves characterizing the source term (the release of hazardous material or energy) and evaluating the resulting impacts on people, equipment, buildings, and the surrounding environment.

Consequence Modeling helps identify the severity of fire, explosion, and toxic release scenarios, forming a critical input to Quantitative Risk Assessment (QRA), Facility Siting Studies, Process Hazard Analysis (PHA), and Emergency Planning.

Ventilation & Dispersion Modeling

External Dispersion

Modeling of toxic or flammable gas/vapor movement in outdoor environments, considering wind, atmospheric conditions, and nearby structures. Used to evaluate concentration contours, offsite impact, evacuation planning, and safe separation distances.

Internal Dispersion

Simulation of gas/vapor buildup inside buildings or enclosures, evaluating ventilation rates, accumulation zones, ignition risk, and HVAC influence. Supports Hazardous Area Classification and detector placement.

Fire Modeling

External Fire Scenarios

Analysis of open-air fires—jet fires, pool fires, flash fires—and their thermal radiation impacts on personnel, equipment, and structures. Supports fireproofing and separation assessments.

Internal Fire Scenarios

Modeling fires inside buildings or compartments, including confined pool fires and equipment fires, evaluating heat buildup, smoke spread, and structural exposure.

Explosion Modeling

External Explosions

Assessment of outdoor explosion scenarios such as VCEs and BLEVEs, generating overpressure contours, structural damage predictions, and safe siting recommendations.

Internal Explosions

Simulation of explosions within enclosed or congested spaces, where confinement increases blast pressure. Used for venting design, building upgrades, and personnel protection.

Frequently Asked Questions (FAQ)

1. Why is Consequence Modeling important?

It provides the technical basis for QRA, Facility Siting Studies, PSM/RMP compliance, emergency planning, and risk-reduction decisions.

2. What types of scenarios can be modeled?

Typical scenarios include toxic gas dispersion, flammable vapor clouds, pool fires, jet fires, flash fires, vapor cloud explosions (VCE), BLEVEs, and internal/external blast events.

3. What is a Source Term?

A source term describes the amount, rate, and conditions under which a hazardous material or energy is released during a Loss of Containment (LOC) event. It defines what is being released, how much, how fast, and in what physical state—forming the starting point for all dispersion, fire, and explosion modeling.

The source term defines the severity of the scenario. All consequence calculations—dispersion clouds, thermal radiation, overpressure, and toxic concentration depend directly on the accuracy of the source term.

4. What are the key elements of source term include?

Material type: toxic gas, flammable vapor, liquid, aerosol, two-phase mixture
Release rate / mass flow: governed by hole size, pressure, temperature, inventory
Release duration: instantaneous, continuous, or time-varying
Release geometry: jet, leak, rupture, vent, choked flow
Physical conditions: phase, temperature, pressure, flashing potential
Location: elevation, orientation, enclosure or outdoor environment

Consequence Modeling