Improving signal passed at danger management in New Zealand rail operations: Combining stabilised approach procedures with risk-triggered commentary driving

The critical examination of driver cognition and information processing is vital to ensuring an effective signal passed at danger prevention strategy. Although this need was identified in KiwiRail’s organisational strategy to reduce signal passed at danger risk, the why and how factors were not clearly described and robustly linked to deliver the necessary effects. With risk-triggered commentary driving programmes gaining recognition as valuable components and activities within the driver competency model, an opportunity to couple risk-triggered commentary driving with stabilised approach methodologies and procedures, adopted from aviation and modified for use on New Zealand’s railway network was subsequently identified. A driver subject matter expert group was formed, a literature review completed, guidance developed and new procedures trialled. This activity provided new opportunities to introduce error-tolerant system design, increase accuracy of driver signal action response and reduce signal passed at danger risk on New Zealand’s National Rail System by adopting and designing bespoke methodologies that support enhanced driver cognition and safe system design.