Fault tree analysis variations

The earliest logic trees were based on engineering fault tree analysis methods. Today, companies use a number of variations or combinations of logic trees and call them by different names, such as Why Tree,< 9) Causal Tree,(20,21) Cause and Effect Logic Diagram (CELD),<22) and Multiple-Cause, Systems-Oriented Incident Investigation (MCS011).<23,24) tools have more similarities than differences. 

ABSTRACT The risks of manufactoring explosives are related to the energy accumulation which is the main property of explosives, and the subsequent risk of its unwanted liberation. Therefore, the risks managements programs and risks assessment tools are very important for explosives manufacturing. So, the main goal of this work is to discuss the suitability of HazOP and Fault Tree Analysis to the explosives industry, as well as propose a variation of HazOp parameters to best suit explosives manufactory... 

This paper presents a new approach based on a combination of traditional predictive modelling and event/fault tree analysis techniques, which allows representing at the same time evolution of hazards and normal and abnormal (i.e. failures) performance of safety measures, e.g. variations of process parameters, analysis and inspections, through the food chain for a better estimation of the real impact of such deviations/failures on consumer health. 

The hazard identification and evaluation of a complex process by means of a diagram or model that provides a comprehensive, overall view of the process, including its principal elements and the ways in which they are interrelated. There are four principal methods of analysis failure mode and effect, fault tree, THERP, and cost-benefit analysis. Each has a number of variations, and more than one may be combined in a single analysis. See also Cost-Benefit Analysis Failure Mode and Effects Analysis (FMEA/FMECA) Fault Tree Analysis (FTA) THERP (Technique for Human Error Rate Probability). 

Fault tree analysis uses a particular set of symbols. Figure 36-4 illustrates commonly used symbols. There are some variations in symbology among practitioners. 

The INRS Model builds on the principles of fault-tree analysis (Leplat, 1978). The model focuses on variations or deviations from the usual course of work at the work-systems level. There are four classes of variations, those related to the individual, the task, equipment and the environment respectively. We here see a clear relation to ergonomic models of work systems. The findings from an accident investigation are displayed in an analytic tree, showing causal relations. Figure 5.9. It gives a schematic presentation... 

Product-line safety assessment typically generalises from individual safety analyses to produce a configurable analysis result that is then customised to the particular product in question. The process may involve annotation of an existing model, such as fault trees (Dehlinger and Lutz 2005), or it may involve the creation of a new model (Stephenson et al. 2004). In contrast to diese relatively simple approaches, (Habli 2009) describes a complex meta-model diat relates design variation, context variation, events, consequences and severities. It is important to note that each of these bodies of work assumes the existence of hazard assessment in-... 

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