The Management Oversight and Risk Tree

A last reference here is the Guide to Use of the Management Oversight and Risk Tree (MORT). In the abstract for that publication, MORT is described as a comprehensive analytical procedure that provides a disciplined method for determining the systemic causes and contributing factors of accidents. This reference to performance errors is of particular interest. 

Guide to Use of the Management Oversight and Risk Tree (SSDC-I03). Washington DC U.S. Department of Energy, November 1994. 

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. 

Most causation models have minimized less than adequate design and engineering concepts and outcomes as a source of causal factors for hazards-related incidents, with one significant exception. That exception is MORT—the management oversight and risk tree. Concepts on which MORT is based have influenced my thinking greatly, and I am indebted to all who worked on the creation and betterment of MORT. 

This causation model puts a major focus on less than adequate management practices that impact on the operations system as a source from which causal factors derive. A borrowing of significance is taken from the Guidelines to Use of the Management Oversight and Risk Tree to emphasize focusing on the system ... 

Or, assume that the causation model is to relate to the concepts on which the management oversight and risk tree is based (a) the system safety idea and (b) an understanding that causal factors may derive from workplace or work methods design. 

Another major approach tends to be very different from other efforts described. The Department of Energy s approach is based on the management oversight and risk tree (MORT), a comprehensive, state-of-the-art program for safety management and system safety. 

Figure 10-2 Analytical trees. (Derived from the student workbook from the Management Oversight and Risk Tree Workshop presented for the Department of Energy by the System Safety Development Center.)...

The management oversight and risk tree (MORT) chart is a large, complex, negative tree (see Chapter 18). Even though the project evaluation tree (PET) is depicted as a positive tree, it is mentally converted and used as a fault tree for accident analysis applications (see Chapter 16). 

The project evaluation tree is an analytical tree to be used primarily as a graphic check in basically the same manner as the management oversight and risk tree (see Chapter 18). The PET chart, however, contains fewer than 200 event symbols and no transfers the MORT chart contains approximately 1,500 events symbols, multiple transfers, transfers within transfers, and drafting breaks. The PET chart is divided into three branches procedures, personnel, and plant and hardware. 

Johnson, William G. 1973. MORT, the MANAGEMENT OVERSIGHT AND RISK TREE. Washington, DC U.S. Atomic Energy Commission. 

Figure 13.1 The management oversight and risk tree (MORT) process.

---