Multilinear event sequencing

Sequentially Timed Events Plot (STEP)<4) is a name used for the multilinear events sequence-based matrix display. It evolved from the 1975 MES concepts, but only events are displayed because conditions or states... 

Event— An occurrence involving the process caused by equipment performance, human action, or by an occurrence external to the risk control system. In Multilinear Event Sequencing (MES) an event is defined as one actor plus one action. 

Benner, Ludwig, Jr., Accident investigations Multilinear events sequencing methods. (June 1975). 

These are but a few of them single event theory chain of events theory epidemiological models systems theory models multilinear events sequencing human factors models life change unit theory motivation-reward satisfaction models and the management oversight and risk tree model. 

Variations in current practice and the need for an accepted investigation methodology were mentioned by Benner in Accident Investigations Multilinear Events Sequencing Methods. Benner writes ... 

To promote learning about incident investigation, Ferry wrote extensively about and suggested inquiry into System Safety, Change Analysis, The MORT Process, Multilinear Events Sequencing, and D. A. Weaver s Technic of Operations Review. 

The event and causal factors charts used by the Department of Energy as an accident (or mishap) investigation tool is basically the same tool as multilinear event sequencing (MES) and similar to simultaneous timed event programming (STEP)—all based on concepts of Ludwig Benner. It is also called causal factors analysis (CFA). 

The basic concept from which event and causal factors charts were developed can probably be traced back to Ludwig Benner and others at the National Transportation Safety Board. Benner developed a very similar technique called multilinear event sequencing (MES) and more recently sequentially timed events plotting (STEP). Event and causal factors charts were part of the overall MORT approach to system safety developed by W. G. Johnson for the Atomic Energy Commission in the early 1970s and further developed and taught by the Department of Energy s System Safety Development Center (SSDC). The use of the event and causal factors chart is sometimes referred to as causal factors analysis. 

Benner, L. (1975). Accidents Investigations - Multilinear Events Sequencing Methods. Journal of Safety Research, 7, 67-73. 

Certain types of deviations within a man-machine system increase the probability of accidents and/or the expected value of loss due to accidents, thus being valid indicators of the accident risk. The nature of accidents represented by the deviation model is based on systems theory, on the energy exchange model, the multilinear events sequencing approach, and concepts of human errors as discussed in chapter 4. 

---