ACSNI [Advisory Committee on the Safety of Nuclear Installations] study group on human factors. Second report: human reliability assessment - a critical overview

Human Reliability Assessment (HRA) is the procedure through which numerical estimates of the probability of human error are made as part of the overall process of Probabilistic Risk Assessment for a nuclear installation. This report by a study group set up by the United Kingdom Advisory Committee on the Safety of Nuclear Installations (ACSNI) examines the growing number of methods of quantifying the probability of human errors in HRA. The study group concludes that HRA is an empirical method, still in its infancy and yielding imprecise but useful results. It has a valid contribution to make if used intelligently and with discretion. Its use is recommended in improving the quality of choice between design alternatives, in identifying tasks where the application of ergonomics and organisational improvements are likely to enhance safety, and as an integral part of the safety assessment of nuclear installations. (UK)