Hazard-Barrier-Target theory

The design of most process plants relies on redundant safety features or layers of protection, such that multiple layers must fail before a serious incident occurs. Barrier analysis ) (also called Hazard-Barrier-Target Analysis, HBTA) can assist the identification of causal factors by identifying which safety feature(s) failed to function as desired and allowed the sequence of events to occur. These safety features or barriers are anything that is used to protect a system or person from a hazard including both physical and administrative layers of protection. The concepts of the hazard-barrier-target theory of incident causation are encompassed in this tool. (See Chapter 3.)... 

There are usually multiple causes of an incident, with multiple people and occurrences contrihuting to its evolution. The Hazard-Barrier-Target (HBT) concept described in Chapter 3 provides an interesting view of the multiple-cause or system theory. 

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