Human Cognitive Reliability Correlation

Human Cognitive Reliability Correlation

Human Cognitive Reliability Correlation (HCR) is a technique used in the field of Human reliability Assessment (HRA), for the purposes of evaluating the probability of a human error occurring throughout the completion of a specific task. From such analyses measures can then be taken to reduce the likelihood of errors occurring within a system and therefore lead to an improvement in the overall levels of safety. There exist three primary reasons for conducting an HRA; error identification, error quantification and error reduction. As there exist a number of techniques used for such purposes, they can be split into one of two classifications; first generation techniques and second generation techniques. First generation techniques work on the basis of the simple dichotomy of ‘fits/doesn’t fit’ in the matching of the error situation in context with related error identification and quantification and second generation techniques are more theory based in their assessment and quantification of errors. HRA techniques have been utilised in a range of industries including healthcare, engineering, nuclear, transportation and business sector; each technique has varying uses within different disciplines.

HCR is based on the premise that an operator’s likelihood of success or failure in a time-critical task is dependent on the cognitive process used to make the critical decisions that determine the outcome. Three Performance Shaping Factors (PSFs) – Operator Experience, Stress Level, and Quality of Operator/Plant Interface - also influence the average (median) time taken to perform the task. Combining these factors enables “response-time” curves to be calibrated and compared to the available time to perform the task. Using these curves, the analyst can then estimate the likelihood that an operator will take the correct action, as required by a given stimulus (e.g. pressure warning signal), within the available time window. The relationship between these normalised times and Human Error Probabilities (HEPs) is based on simulator experimental data.