Page - 1519 - in Book of Full Papers - Symposium Hydro Engineering

because we are naturally disposed towards analysis and it is easier to operate where numbers are available? This paper explores the source of soft risks and attempts to learn lessons by reference to previous studies into fields such as finance, corporate governance and accident investigations. As such, it explores “Human Factors” relating to individuals, groups and organisations. In case there is any doubt as to the need to explore the non-technical issues, we quote below an extract from the Oroville Investigation into the failure of the spillway: “The fact that this incident happened to the owner of the tallest dam in the United States, under regulation of a federal agency, with repeated evaluation by reputable outside consultants, in a state with a leading dam safety regulatory program, is a wake-up call for everyone involved in dam safety.” 2. HOW PREVALENT ARE SOFT RISKS? In order to make an immediate case as to the importance of soft risks reference is made to a number of areas, starting with accident investigations. The United Kingdom’s Health and Safety Executive (HSE) in their evidence to a parliamentary science and technology committee previously stated that: “It has been estimated that 90% of all workplace accidents have a human error as a cause” Indeed, human error was cited as a significant constituent in many of the notorious industrial accidents, which have led to subsequent independent enquiries. The following examples are quoted as examples of incidents/accidents with a strong human influence: Accident, Industry and Date Consequences Human Contribution Three Mile Island, Nuclear Industry 1979 Serious damage to core of nuclear reactor Operators failed to diagnose a stuck open valve due to poor design of control panel, distraction of 100 alarms activating and inadequate operator training. Maintenance failures had occurred before, but no steps had been taken to prevent them recurring. 1519