Appendix A: Theoretical risk overview

Risk is the likelihood of damage or loss from the hazard, integrated across the entire spectrum of possible events:

Risk = f (likelihood, impact).

Impact is based on the interaction of the fire characteristics and the vulnerability of the asset to fire.

Impact = f (hazard, exposure, vulnerability).

The direct impact of the event is calculated from the costs modelled across all exposures during the event. If we examine the elements of impact:

  • Hazard is a physical situation with a potential for undesirable consequences to people, property or the environment. It refers to the fire, accident or incident that the fire service is responding to.
  • Exposure refers to what elements are at risk such as: people, buildings, infrastructure, agriculture etc.
  • Vulnerability refers to how each exposed element responds to the level of hazard. Vulnerability can be divided into four main areas: physical, social, economic and system.