Safety issue
Manual systems of train management, such as Special Proceed Authority working, are used when interlocked/engineered systems are not available. However, manual systems are subject to human error and increase the risk of safeworking irregularities/incidents when compared to interlocked/engineered systems of safeworking.
Response from the ARTC
Special Proceed Authorities (SPAs) are a paper-based safe working system, not unlike Train Orders. Paper-based systems such as Train Orders are used to authorise train movements over a significant part of Australia's national rail network. The incident at Tarana occurred in the execution of the SPA, not as a result of a problem with the safe working system.
ATSB assessment of response
The Australian Transport Safety Bureau notes ARTC's response, however the risk of safeworking irregularities is greater with manual systems of safeworking. The ATSB urges the ARTC to explore further opportunities to mitigate the risks of human error when using a paper-based system in addition to considering alternative risk controls that may reduce or eliminate human error.
Safety recommendation
The Australian Transport Safety Bureau recommends that the ARTC take action to address this safety issue.