Fire loss is usually measured as number of deaths or dollars of property damage, but includes significant intangible losses such as business interruption, mission failure, degradation of the environment, and destruction of irreplaceable cultural artifacts. The concept of safety itself is one of uncertainty. Absolute safety does not exist. Human activity will always and unavoidably involve risks. The concept of fire is also uncertain.
Unwanted combustion is perhaps the least predictable common physical phenomenon.
Reliability of manufactured or fabricated systems for fire suppression and confinement is another source of uncertainty or risk. To make meaningful decisions regarding these risks, it is necessary that they be analyzed. In fire safety we most often rely on empiricism and intuitive heuristics to make decisions. Increasing computational capabilities and modeling techniques from fields such as decision analysis, management science, operations research, and systems safety now allow us to identify the framework or structure of our decision making process, with varying levels of mathematical sophistication. Fire Risk Analysis is a generic phrase that covers many approaches to decision making about the uncertainties of losses from fire.