Risk Analysis

Risk is the combination of the likelihood of some unwanted event happening, combined with the severity of its consequences.

Risk in general is the combination of all the risks of individual events.

Analysing the risk with the deployment of safety-critical or mission-critical systems is not only sound engineering but often legally required.

To Risk Analysis belongs Hazard Analysis and Assessment of Likelihood.

Hazard Analysis:

The identification of unwanted events or system states, and possible consequences of these unwanted situations. Such methods as FMEA or FMECA are traditionally used.

Assessment of Likelihood:

Traditional methods such as Fault-Tree Analysis (FTA) require significant probabilistic assumptions such as the independence or non-interaction of events, which are often very difficult to establish.

Newer approaches to Risk Analysis avoid this issue by classifing likelihood as well as severity of unwanted events into five to six discrete categories and concentrating on making a watertight case for the resulting classification.