System safety causation models based

Systemic Socio-Technical Causation Model for Hazards-Related Incidents At least 25 incident causation models are referenced in safety literature. They present a great diversity of thinking. None of those models have achieved anything close to universal acceptance. Yet, safety professionals are obligated to have the advice they give be effective as clients take action to avoid, eliminate, or control hazards and to achieve acceptable risk levels. That advice must be based on a sound and studied thought process that takes into consideration the reality of the sources of hazards. This author builds a case in support of what he proposes for a systemic sociotechnical causation model for hazards-related incidents. 

It is a necessity that the advice given by safety professionals be based on an understanding of the reality of causal factors and actually serves to attain a state for which the risks are judged to be acceptable. I will develop a systemic causation model for hazards-related occupational incidents that represents the thoughts set forth in this chapter. 

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. 

Creating a richer model of causation. (Leveson and Dulac 2005) propose the STAMP accident model and the STPA hazard assessment approach. STAMP is based on systems-theoretic concepts of hierarchical control, internal models of the environment and a classification of control errors. STPA takes that classification as the basis for iterative integrated control system safety assessment. At each design iteration the design is assessed and constraints are derived (equivalent to derived safety requirements) and imposed on further design iterations. 

The use of standardized terminology is required across all industries and professions so that people working in prevention will have better access to relevant and meaningful data on causation factors. Effective risk cormnunication expressed through clearly defined terms and simplified models is needed to assist in meaningful event analysis. The establishment of safe systems of work is not possible until our safety initiatives come to be based on valid and rehable data. 

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