Widening the scope of human factors safety assessment for decommissioning

In the nuclear industry, throughout the lifecycle of a nuclear plant or facility, operations vary in the degree of their tractability. Commissioned facilities should be relatively predictable in their operations, whereas decommissioning operations by their nature tend to be less predictable because they are a transition from one state to another, where safety systems, structures, components, and people serving safety may all change. Of course, different operations or states will have different characteristics and varying safety requirements. In this paper, we argue that by accounting for operations according to their relative tractability for their given phase in the lifecycle of a facility, a more targeted approach to managing safety is possible—one that recognises that the less tractable operation relies on human adaptation and resilience to a greater degree than the more tractable operation. From the outset, the safety of a decommissioning operation may therefore require a thorough account of the human and organisational factors that will support or impair human adaptation and resilience. High Reliability Organisation theory may provide a useful framework to consider how to engineer resilience in decommissioning and other operations of a less tractable nature.