Technical details
Transport for New South Wales


Human Factors
New South Wales

Following the Waterfall Rail Disaster in 2003, one of the key recommendations from the McInerney inquiry was the introduction of an Automatic Train Protection (ATP) system.


In Sydney an ETCS Level 1 Limited Supervision (LS) system was selected as a transitional system between the existing fixed-block trackside signalling system and the future adoption of ETCS Level 2.

In the Level 1 LS system a driver continues to observe lineside signals and speed signs, and existing driver safety systems are maintained. The ATP system uses fixed track mounted balises to provide Ceiling Speed Monitoring (CSM) against permitted line speed, Target Speed Monitoring (TSM) for high risk speed reductions, and Electronic Train Stops (ETS) for all signals not currently protected by mechanical train stops.

As a transitional system, the ATP solution sought to retain existing driver practices wherever possible, whilst providing safety benefits and enabling future network performance improvements though the introduction of ETCS Level 2. These goals present a number of human factors challenges, as many aspects of the solution must be compatible with the different use cases associated with Level 1 LS and Level 2 Full Supervision.



SYSTRA Human Factors (HF) personnel formed part of the TfNSW Operational Readiness team to provide system level HF assurance and help prepare Sydney Trains for the introduction of ETCS Level 1.

Working alongside SYSTRA ETCS Engineers, the human factors specialists gained an in-depth understanding of the system architecture and functions. This knowledge was used to conduct detailed analysis system functionality within the New South Wales rail context, and to manage consistency in onboard solutions provided by different ETCS suppliers.

SYSTRA human factors specialists provided input to the development of trackside design principles and evaluated the impact on the driver and overall system safety.

We completed a comprehensive analysis of onboard and trackside maintenance tasks to identify potential human errors and inform design changes and procedural controls. We also conducted Risk Based Training Needs Analysis (RBTNA) to identify training needs and priorities for onboard and trackside maintainers.

SYSTRA developed human factors testing specifications and completed testing activities to evaluate system performance, explore potential human factors issues, and provide assurance against system requirements.


Working as part of a wider team of SYSTRA ETCS experts, our human factors specialists gained a detailed technical understanding of the overall ETCS solution. This enabled our team to complete complex analyses and achieve the best possible outcome for our client.

SYSTRA personnel facilitated engagement with Sydney Trains maintenance representatives to provide end-user input to maintenance human error assessments, develop maintenance processes and procedures, and to design training solutions. This enabled the smooth introduction of ETCS equipment for maintenance personnel and an efficient risk based approach to training.