Abstract
Rail shunting, the process of making up or breaking up of trains, is a complex high-risk work activity in a rigid working environment and presents multiple safety challenges. New Zealand rail shunting accidents that result in worker injuries have been increasing in recent years despite increased regulatory intervention. International research into shunting safety has been extremely limited to date and there has been no New Zealand research on this. Two human factors analysis methodologies, Cognitive Work Analysis and AcciMap, were used in this thesis. These proven research methodologies are not domain specific and have been used in several high-risk domains like aviation, defence and transport, so are well suited to examine shunting. The research aims were to gain an understanding of how workers manage the boundaries of safe working in the shunting domain.
The research findings demonstrated that the adaptability of the workers was an essential element of safe working and that there is a gap between task theory (work as imagined) and task reality (work as done). This reinforces the concept that safety must be designed at the start of the planning phase of ‘work’ as opposed to the ‘delivery’ phase of work. New Zealand’s rail system contains many complexities and conflicts, which result in overreliance on sharp-end rules and procedures to maintain safety.
The research has contributed to a broader understanding of safe working in the railway shunting domain, including suggestions for reducing system complexity to improve shunting safety and efficiency.