Quantifying the Metrics that Characterize Safety Culture of Three Engineered Systems


With potential energy shortages and increasing electricity demand, the nuclear energy option is being reconsidered in the United States. Public opinion will have a considerable voice in policy decisions that will "roadmap" the future of nuclear energy in this country. This report is an extension of the last author's work on the "safety culture" associated with three engineered systems (automobiles, commercial airplanes, and nuclear power plants) in Japan and the United States. Safety culture, in brief is defined as a specifically developed culture based on societal and individual interpretations of the balance of real, perceived, and imagined risks versus the benefits drawn from utilizing a given engineered systems. The method of analysis is a modified scale analysis, with two fundamental eigenmetrics, time- (τ) and number-scales (N) that describe both engineered systems and human factors. The scale analysis approach is appropriate because human perception of risk, perception of benefit and level of (technological) acceptance are inherently subjective, therefore "fuzzy" and rarely quantifiable in exact magnitude. Perception of risk, expressed in terms of the psychometric factors "dread risk" and "unknown risk", contains both time- and number-scale elements. Various engineering system accidents with facilities, reported by mass media are characterized by τ and N, and are presented in this work using the scale analysis method. We contend that level of acceptance infers a perception of benefit at least two orders larger magnitude than perception of risk. The "amplification" influence of mass media is also deduced as being 100- to 1000-fold the actual number of fatalities/serious injuries in a nuclear-related accident.


Nuclear Engineering and Radiation Science

Keywords and Phrases

Engineered systems; Level of acceptance (LOA); Number-scales; Perception of benefit (POB); Perception of risk (POR); Safety culture; Time-scales

Document Type

Article - Conference proceedings

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Publication Date

19 Oct 2002