AS 7507 Rolling Stock Outlines

The objective of this Standard is to define the requirements for assessing whether the physical size and predicted kinematic behaviour of candidate rolling stock comply with the rolling stock outlines specified by the Rail Infrastructure Manager (RIM).

The review modernises and expands the framework for rolling stock outlines, with a moderate impact on organisations already using the previous version. Key changes include clearer distinctions between different types of outlines, such as static and kinematic, with improved definitions and assessment methods. The Standard introduces enhanced guidance on design verification, including testing and simulation-based approaches. It also updates reference vehicle data to align with current network practices and allows controlled combinations of vehicle features. In addition, it strengthens requirements for maintenance, record keeping and hazard management, including clearer links to outline-related risks such as out-of-gauge events.

The Standard manages risks associated with rolling stock exceeding allowable clearances. These include out-of-gauge trains striking infrastructure, overhead systems or other trains, which can result in incidents such as sideswipes or turnout fouling. It also addresses risks caused by modifications, suspension changes or degraded conditions that may affect vehicle dimensions. Additional risks include excessive dynamic movement, such as sway or roll, leading to clearance loss on curves or transitions. The Standard also considers risks from poorly controlled maintenance or infrastructure equipment operating outside agreed limits. Managing these risks supports safer operation across the network.

The Standard provides a structured method for assessing rolling stock outlines using defined reference outlines and vehicles. It covers both static and dynamic conditions, including kinematic and swept envelopes, to reflect how trains behave in operation. It also clarifies roles and responsibilities between rolling stock operators and rail infrastructure managers for assessment and verification. A key feature is its strong link to hazard management, connecting outline requirements and verification processes to known risks. The Standard also supports consistent application by providing defined methods, reference data and expectations for ongoing assurance.

The Standard improves safety by requiring structured assessment and verification of rolling stock outlines against defined reference vehicles and route conditions. This reduces the likelihood of clearance-related incidents, such as out-of-gauge movements. It also supports interoperability by standardising the terminology, methods and reference outlines used across rail networks. This consistency allows rolling stock to be assessed and approved more reliably for operation across different networks. By aligning approaches between rolling stock operators and infrastructure managers, the Standard helps ensure safe and compatible operation across the rail system.

The Standard can be implemented by aligning existing vehicle acceptance, modification and route access processes with its outline assessment and verification requirements. Organisations should update engineering procedures and tools to assess rolling stock against defined reference vehicles and document key assumptions and calculations. Outline verification and testing should be integrated into maintenance and asset management plans, with clear triggers for reassessment. Strong record keeping and configuration control are also required, including maintaining data, approvals and hazard records. Clear coordination between rolling stock operators and infrastructure managers is essential to manage outline requirements and risks effectively.