QRA is a technique used to systematically calculate the risks from hazardous events. It involves predicting the size of consequences associated with a hazard, and the frequency at which a release of the hazard may be expected to occur. These aspects are then combined in order to obtain numerical values for risk – usually risk of fatality.
QRA includes consideration of all identified hazardous events in order to quantify the overall risk levels. Similar hazardous events are often grouped and assessed together as bounding or representative events.
Methodology Link: https://www.hse-rms.com/blog/methodology-for-qra-study