Citation

Goossens LHJ, Cooke RM. Safety Sci. 1997; 26(1-2): 35-47.

Copyright

(Copyright © 1997, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Risk assessments are carried out as a support for decision making on major hazards activities. The risk assessments are explanatory in nature and are not aiming at predictions of accidents which might occur. In various areas a lot of experience has been gained with risk assessments, for which well known techniques (like FMEA, fault trees and so forth) are applied. In quantifying risks, the prior position is often a scarce amount of necessary data on component failures or specific phenomena. The decision to pick the 'right' numbers is therefore limited. There is felt a need to collect data with other techniques as well. The paper describes two Such techniques: 1. (i) a formal expert judgement technique to establish quantitative subjective expert assessments on design and model parameters2. (ii) a system failure analysis technique (Accident Sequence Precursor Methodology) which uses operational evidence of system failures to derive the system failure probability of the system as a whole. For both techniques an example case is presented for illustration.