Qualitative & Quantitative Risk Assessment (QRA)

Risk Assessment in process and industrial settings involves evaluating the likelihood and consequences of hazardous events to determine whether risks are acceptable and what controls are required. It is conducted at two levels — qualitative and quantitative.

Qualitative Risk Assessment uses structured methods such as risk matrices and consequence- likelihood tables to rank risks and prioritise controls — without requiring detailed numerical modelling. Quantitative Risk Assessment goes further — using mathematical models to estimate the probability and magnitude of harm, expressed as individual risk, societal risk, or other quantitative measures.

QRA is used to support facility siting decisions, land use planning, safety case development, and regulatory submissions — in chemicals, oil and gas, petrochemicals, and other high-hazard industries where risk-informed decision making is required.