Quantitative / Probabilistic Risk Assessment

At PID, we deliver high-integrity quantitative and probabilistic risk analyses to support our clients in understanding and managing risks throughout complex industrial environments. Going beyond qualitative screening, these studies quantify the severity and likelihood of hazardous events and provide a rigorous foundation for defensible decision-making.

Our quantitative risk analyses (QRA) estimate the risk by integrating validated consequence modeling, event frequencies, and vulnerability correlations. These are used to calculate individual and societal risk levels, fire and explosion risk contours, and fatality probability thresholds. Typical outputs are risk metrics that guide land use planning, building siting, and mitigation / escalation prevention strategies. We rely on industry-standard tools like DNV’s SAFETI aligned with best practices from CCPS, ISO 31010, and regional regulatory guidelines.

Our probabilistic risk assessments (PRA) provide a deeper system-level perspective, analyzing how combinations of equipment failures, human errors, and latent conditions could defeat critical safeguards. PRA involves techniques such as fault tree and event tree analysis, common cause failure modeling, and Monte Carlo simulation to evaluate the reliability of safety systems. These methods are particularly relevant to high-integrity applications, including shutdown systems for deepwater wells, subsea isolation valves, and complex emergency response functions. Tools such as RiskSpectrum or custom reliability models are used depending on the system architecture.

Our services include:

• Full-scope quantitative risk assessment (QRA)
• Fire and explosion risk assessment (FERA)
• Occupied building risk assessment (OBRA)
• Temporary refuge impairment assessment (TRIA)
• Individual and societal risk contour mapping
• Frequency estimation of hazardous events (failure rate databases, historical data)
• Consequence modeling integration (fire, explosion, toxic dispersion, external objects impact energy)
• Escalation risk analysis for critical infrastructure
• Ship collision risk assessment
• Dropped object impact risk assessment
• Probabilistic Safety Assessment (PRA) using fault tree and event tree analysis
• Common cause failure modeling and dependency analysis
• Monte Carlo simulation for safety function reliability
• Scenario-specific risk ranking and tolerability evaluation
• Cost-benefit and ALARP justification for risk reduction measures
• Sensitivity analysis and uncertainty quantification
• Risk-informed decision support for layout, protection, and mitigation
• Compliance demonstration with regulatory risk criteria
• Training courses