The rail industry is entering a period of rapid technological change. Across Australia and globally, operators and manufacturers are exploring new propulsion technologies to decarbonise rail operations, reduce emissions and improve operational efficiency.
Battery-electric locomotives are already entering service, while hydrogen traction continues to be explored as a potential pathway to lower-emissions freight operations.
These innovations present enormous opportunities to improve productivity for the industry. But they also introduce new technical risks that must be carefully managed.
Fire safety is one of the most critical of these.
To support the safe adoption of emerging technologies while maintaining a consistent national safety framework, ARISO has released a significantly updated version of AS 7529.1 Rolling Stock Fire Safety: Locomotives and Freight.
One of eight standards identified as the priority for updating by The Track to Decarbonised Rolling Stock report commissioned by ARISO in 2024, the revised Standard provides a contemporary approach to fire risk management for modern rolling stock, including vehicles incorporating battery and hydrogen technologies.
Importantly, the update strengthens both safety outcomes and national harmonisation – two priorities at the centre of Australia’s evolving rail system.
A new era of propulsion
The momentum behind alternative traction technologies is growing.
In early 2026, Fortescue received its first battery-electric locomotives for operations in the Pilbara, while Aurizon is preparing to conduct a Battery Electric Tender (BET) trial on Alcoa’s Kwinana to Pinjarra route in Western Australia. Hydrogen traction is also under investigation in Australia, reflecting international developments where hydrogen fuel cells are being tested as a viable alternative to diesel.
These technologies are central to the industry’s decarbonisation ambitions, but they introduce new fire and explosion behaviours that differ significantly from traditional diesel systems.
The Track to Decarbonised Rolling Stock report, for which ARISO partnered with engineering consultancy Jacobs, examines how net-zero technologies could impact existing rolling stock standards. It identifies several areas where the standards framework would need to evolve to ensure new propulsion systems could be deployed safely.
A unified approach to fire safety
One of the key changes in the updated Standard is the integration of AS 7529.2 into AS 7529.1, creating a single consolidated reference for locomotive fire safety.
Previously, the two documents addressed related but separate aspects of fire safety requirements. Combining them now provides a clearer, more accessible framework for designers, manufacturers and operators – particularly for locomotives that use battery or hydrogen tenders.
Further, ARISO is proactively addressing how these risks can be managed. Through the use of this Standard, a harmonised approach can be taken, assisting first responders in understanding what measures have been taken before attending any incident.
“Rolling stock technology is evolving rapidly, particularly as the industry moves toward lower-emission propulsion systems,” said Cris Fitzhardinge, Senior Standards Development Manager at ARISO.
“This update ensures the fire safety framework keeps pace with those changes. By bringing the requirements together into a single Standard and addressing new propulsion technologies directly, we’re providing industry with clear guidance to manage emerging risks while supporting innovation.”
The revised Standard establishes the minimum level of fire safety required for locomotives and freight rolling stock operating in Australia, supported by performance-based requirements and deemed-to-satisfy solutions.
This approach allows operators and manufacturers flexibility in how they meet the Standard while ensuring consistent safety outcomes across the national network.
Managing new and complex risks
Historical incidents, such as the Sofia-Kadam train fire in Bulgaria in 2008 or the commuter train fire in Valhalla, New York in 2015, which have resulted in multiple fatalities, demonstrate how rapidly an onboard fire can escalate if not properly controlled through design, materials and safety systems.
The updated AS 7529.1 continues to manage the traditional hazards associated with fire ignition, fire spread and safe evacuation. At the same time, it introduces a comprehensive framework for the unique risks presented by zero-emission propulsion technologies.
In total, the Standard addresses twelve existing fire hazards while identifying twelve new hazards specific to battery and hydrogen technologies.
These include risks such as thermal runaway within battery systems, the propagation of fire between battery cells, the release of flammable or toxic gases, pressure build-up within battery enclosures, high-velocity flame events during system rupture, and the potential for re-ignition after suppression.
Hydrogen propulsion presents its own unique challenges, including hydrogen leakage, accumulation in confined areas and the difficulty of visually detecting low-luminosity hydrogen flames.
Together, these hazards highlight the complex fire behaviours associated with next-generation rolling stock technologies and the importance of robust engineering controls.
The updated Standard provides requirements and recommendations to ensure rolling stock is designed and maintained to:
• reduce the likelihood of fire ignition
• control fire growth and spread
• minimise the impact of fire on crew and operations
• support safe evacuation and emergency response.
Harmonisation across the national network
Beyond safety, the Standard also plays an important role in supporting harmonisation across Australia’s rail system.
As locomotives increasingly operate across multiple jurisdictions and networks, consistency in core safety requirements becomes essential.
A harmonised national approach helps improve incident response, reduce duplication, streamline rolling stock approvals and provide clarity for manufacturers designing equipment for the Australian market.
“Consistent national standards are fundamental to interoperability,” Fitzhardinge said.
“By providing a clear and contemporary fire safety framework that applies across networks, this Standard helps ensure new and existing locomotives can operate safely and efficiently wherever they run.”
This alignment is particularly important as operators transition to mixed fleets, where traditional diesel locomotives operate alongside emerging zero-emission technologies.
Enabling innovation while protecting safety
The rail industry’s transition toward cleaner propulsion technologies is accelerating. But innovation can only succeed if safety frameworks evolve alongside it.
The updated AS 7529.1 Rolling Stock Fire Safety: Locomotives and Freight ensures that as the industry moves toward battery and hydrogen traction, the risks associated with these technologies are clearly understood and effectively managed.
By strengthening fire safety requirements while maintaining a consistent national framework, the Standard provides a critical foundation for the safe introduction of next-generation rolling stock. And in a rapidly changing rail landscape, that foundation has never been more important.
