Evaluation of a task performance resource constraint model to assess the impact of offshore emergency management on risk reduction

In this age of safety awareness, technological emergencies still happen,occasionally with catastrophic results. Often human intervention is the only way ofaverting disaster. Ensuring that the chosen emergency managers are competent requires acombination of training and assessmentH. owever, assessmenct urrently relies on expertjudgement of behaviour as opposed to its impact on outcome, therefore it would bedifficult to incorporate such data into formal Quantitative Risk Assessments (QRA).Although there is, as yet, no suitable alternative to expert judgement, there is aneed for methods of quantifying the impact of emergency management on risk reductionin accident and incidents.The Task Performance Resource Constraint (TPRC) model is capable ofrepresenting the critical factors. It calculates probability of task success with respect totime based on uncertainties associated with the task and resource variables. The resultscan then be used to assess the management performance based on the physical outcomein the emergency, thereby providing a measure of the impact of emergency managementon risk with a high degree of objectivity.Data obtained from training exercises for offshore and onshore emergencymanagement were measured and successfully used with the TPRC model. The resultingprobability of success functions also demonstrated a high level of external validity whenused with improvements in emergency management or design changes or real data fromthe Piper Alpha disaster. It also appeared to have more external validity than otherHRQ/QRA techniques as it uses physical data that are a greater influence on outcomethan psychological changes - though this could be because the current HRA/QRAtechniques view human unreliability as probability of error rather than probability offailure. The simulation data were also used to build up distributions of timings for simpleemergency management tasks. Using additional theoretical data, this demonstrated themodel's potential for assessing the probability of successf or novel situations and futuredesigns.