Assessment of risk modification due to safety barrier performance degradation in Natech events

Barriers Involved in the Safety Management Systems: A Systematic Review of Literature

“…If the uncertainty increases further, the L-2 assessment would be applied to identify the modified performance of the safety barrier by means of FTA. Different from the three-level methodology proposed by Misuri et al [ 21 ], Dimaio et al [ 74 ] did not emphasize the calculation of the baseline performance of the safety barrier, as shown in Figure 13 b, they paid more attention to the barrier performance variation caused by the varying conditions. The foundation for the study of Dimaio et al [ 74 ] is the assumption that the health state (HS) can be utilized to represent the safety barrier performance in the aspects of judging whether the designed barrier function is fulfilled or not.…”

“…To evaluate the performance of safety barriers in the oil and gas industry, Johansen and Rausand [ 72 ] proposed several points that can be used to conduct a barrier performance assessment, and the performance of safety barriers designed for gas drilling operations [ 73 ], offshore installations in harsh environments [ 46 ], the functioning of slug catchers [ 74 ] and offshore drilling blowouts [ 75 ] are evaluated. Inspired by the work conducted by [ 37 , 76 ], similar indicators to assess the safety barrier performance were designed for Natech scenarios, and the same indicators were also applied by Misuri et al [ 21 , 65 ] to analyze the performance degradation of safety barriers and the role of safety barriers in mitigating domino scenarios caused by Natech events. The indicators or aspects used to perform an assessment of safety barriers are summarized in Table 4 , and their application scenarios are also involved.…”

“…Harsh or adverse conditions or events may deteriorate the performance of safety barriers or critical safety elements, regardless of whether they are active or passive [ 46 ]; as a result, the protection provided and the possibility of preventing cascading effects may be reduced [ 21 ]. Although it is generally recognized that safety barriers with deteriorating performance markedly increase the likelihood of an accident [ 65 ], to date, no methodologies have been proposed to accurately quantify the degradation mechanism of safety barriers.…”

“…The newly available KID is utilized to analyze the performance degradation of barriers by using a statistical-based dynamic risk assessment [ 94 ], a hidden Markov Gaussian mixture model [ 95 ] and a time-dependent reliability analysis [ 74 ]. Inspired by the abovementioned studies, more recently, the performance degradation of safety barriers was investigated quantitatively by [ 21 , 74 ] based on the perspectives of multilevel quantification of barriers and multistate Bayesian inference, respectively. The general principle for these two methodologies is compared and illustrated in Figure 13 .…”

“…Based on the general classification of safety barriers as preventive and protective, the Bow-tie diagram is combined with safety barriers [ 15 ]; as a result, the concept of barrier management is first initiated and applied in the rig industry [ 16 ]. The functions of safety barriers in preventing the possibility of issues and attenuating the consequences of accidents have been verified in various industries, such as offshore oil and gas [ 17 ], fire prevention [ 18 ], nuclear power [ 19 ], maritime shipping [ 20 ], Natech (natural-hazard-triggered technological) events [ 21 ] and road transportation [ 22 ]. According to Puisa et al [ 8 ], as illustrated in Figure 2 , different kinds of safety barriers are applicable for specific industrial scenarios; for instance, in the offshore oil and gas industry, mitigative safety barriers are more popular, while preventive safety barriers are preferred in the railway industry.…”