Risk Assessment: Tools, Techniques, and Their Applications

1.1 Terminology

Risk assessment terminology will be presented throughout the book. However, at this time, several key terms will be defined.

Risk has been defined in many ways, and for the purposes of this book, risk is defined as the probability of an unwanted event that results in negative consequences. Kaplan and Garrick use a set of three questions to define risk (11).

1. What can go wrong?

2. How likely is it?

3. What are the consequences?

Chapter 2 of this book defines risk in depth.

Probability is defined as a measure of how likely it is that some event will occur (12).

Hazard is defined as a source of potential damage, harm, or adverse health effects on something or someone under certain conditions at work (13).

Severity is defined as the degree of something undesirable (12).

Consequence is defined as the effect, result, or outcome of something occurring earlier (12).

Vulnerability is defined as a weakness in a system or human that is susceptible to harm (12).

Threat is defined as a source of danger (12). Threat and hazard are considered analogous.