QUASA: A method for assessing the quality of safety analysis

Abstract

Rouhiainen, V., 1992. QUASA: A method for assessing the quality of safety analysis. Safety Science, 15:155–172 The increasing application of safety and risk analysis makes it necessary to have methods and criteria for evaluating the contents and results of such analyses. The main problems encountered in the applicability of safety analysis are the quality of the analyses and the resources needed for the analyses. Quality systems developed for other industrial purposes offer means for developing systems which support the quality management of safety analysis. These issues constitute the subject matter of this investigation. This paper describes a new method for assessing the quality of safety analyses. The method is based on evaluation of the analysis process and identification of its deficiencies by means of a checklist. For validating the method, the interassessor reliability has been examined by conducting parallel independent assessments of the same safety analysis. The validity of the method in uncovering deficiencies in the safety analysis was examined by using information on critical incidents collected from the analysed activity and descriptions of accidents as the reference. The importance of the observed deficiencies was evaluated by taking the effect of the incidents on safety as the criteria. The results of the study demonstrated that this new method is capable of revealing most of the significant deficiencies in a safety analysis.