Across Australia, transport hubs - often referred to as Transit-oriented developments (TODs) - have become a defining feature of contemporary urban growth

Across Australia, transport hubs – often referred to as Transit-oriented developments (TODs) – have become a defining feature of contemporary urban growth.

Major rail and metro investments are increasingly accompanied by dense, mixed-use precincts that combine transport infrastructure with retail, residential, commercial and civic functions. These developments are no longer just buildings near stations. They are complex, multi-level urban ecosystems which operate at extremely high occupancy levels.

While planning discussions around TODs often focus on land use, transport integration and placemaking, fire safety is usually treated as a background compliance issue. In practice, however, TOD architecture introduces a set of fire engineering challenges that are fundamentally different from those which are encountered in conventional standalone buildings. As Australian cities continue to densify around transport hubs, it is time to ask whether our fire safety approaches are keeping pace and what we might learn from international experience. Of particular importance is the integration of active suppression systems such as sprinklers.

Why TODs are a different fire safety problem

Modern TODs are characterised by architectural and operational complexity. Stations are integrated into podiums, towers are stacked above retail and concourse levels and public circulation frequently passes through privately owned spaces. Underground stations and concourses introduce long travel distances and enclosed environments. Elevated decks and developments built above rail lines (using “air-rights”) connect multiple buildings into a single pedestrian network.

For example, in Victoria, the Government has the Activity Centre Program which is focussed along transport corridors and key rail stations. The program aims to achieve greater densification of housing and other retail, commercial and parking activities. In some cases, this involves high rise developments of up to 20 storeys.

From a fire engineering perspective, these conditions blur the boundaries between different buildings. Evacuation paths are shared, smoke can migrate across interconnected volumes, and peak occupant loads are driven not only by building use but by transport operations and passenger surges. Traditional building-by-building fire safety design approaches struggle to adequately reflect how people actually move through these precincts.

Automatic sprinklers are central to managing TOD fire risks. They reduce fire severity, limit smoke and extend safe evacuation times in large public spaces such as concourses and podiums. Australian Standards (AS 2118 series) and the National Construction Code (NCC) performance-based solutions increasingly recognise sprinklers as enabling alternative egress strategies and protecting interconnected precincts.

Two countries that illustrate different responses to this challenge are Japan and Australia.

Japan: fire engineering at the precinct scale

Japanese metropolitan TODs represent some of the largest and most integrated station developments in the world. In cities such as Tokyo and Osaka, major stations are embedded within dense mixed-use complexes that combine retail, offices, hotels and residential towers above and around active rail corridors. Underground shopping streets and pedestrian tunnels can extend for kilometres, linking multiple operators and developments into a continuous public interior.

In this context, fire safety is not treated as a series of isolated building problems. Japan’s regulatory framework explicitly supports performance-based fire engineering under the Building Standard Law and the Fire Service Act. This allows safety to be assessed at the scale of entire complexes rather than individual buildings or tenancies.

Evacuation planning typically considers interconnected concourses, podiums and decks as unified domains. This reflects real passenger movement patterns. Multiple protected vertical routes are provided across several levels. This allows people to move up, down or laterally in order to reach safety as may be required depending on location and conditions.

Smoke control is a dominant design driver, particularly in underground environments. Large-scale extraction systems, pressurised stairways and carefully zoned smoke reservoirs are coordinated with architectural geometry. Compartmentation between station areas, retail podiums and tower cores limits fire and smoke spread without disrupting everyday .

Active suppression is fully integrated in Japanese TODs. Sprinklers complement smoke control by limiting fire growth, heat, and compartment temperatures. This allows mechanical extraction to work effectively and protects occupants and infrastructure. Private railway operators ensure ongoing maintenance and inspection of sprinklers, alarms, and other fire systems.

Crucially, many Japanese TODs are developed and operated by private railway companies acting as long-term custodians of entire precincts. This operational continuity supports integrated maintenance, inspection and emergency management. The result is that fire safety is embedded into the life of the precinct rather than being frozen at design approval.

Australia: Podiums, towers and public realm

Australian TODs have expanded rapidly over the past decade and are expected to grow further. Architecturally, they tend to adopt podium-and-tower typologies. This involves retail and station-related functions at lower levels and residential or commercial towers above.

Unlike Japan, Australian TODs are often delivered through staged, multi-stakeholder development. Different developers contribute individual sites under a government-led precinct framework, and integration typically occurs through streets, plazas and forecourts rather than continuous internal concourses. Underground environments are generally limited to station infrastructure rather than extensive commercial networks.

Fire safety in these developments is regulated primarily through the NCC, supported by Australian Standards and state-based controls. In many cases, prescriptive compliance is sufficient. However, TOD conditions frequently trigger performance-based solutions. This is particularly the case where stations interface with private buildings, large podiums serve multiple towers or evacuation relies on shared public spaces.

Sprinklers are increasingly used in performance-based solutions. They reduce fire severity, extend safe egress and provide flexibility in shared circulation. Podiums serving multiple towers often rely on sprinklers to manage high occupant loads and complex evacuation paths. NCC guidance supports their use to protect life and reduce structural risk in hybrid-use TODs.

Fire engineering effort is often concentrated at these interfaces. This includes managing compartmentation between public and private areas, ensuring evacuation capacity during peak mixed-use occupancy and maintaining emergency vehicle access within highly designed public realms. For larger precincts, overarching fire strategy frameworks are sometimes used to maintain consistency across staged delivery.

Australian practice remains strong. However, increasing density and more interconnected developments mean that fire engineering now requires coordination at the broader, precinct‑level. This is similar in some ways to the aforementioned approach used in Japan.

Enter AI: from static compliance to living systems

Both Japanese and Australian approaches are fundamentally design-stage focused. Fire safety is largely demonstrated through documents, models and calculations prepared at a point in time. Once a development is operational, the original assumptions often fade into the background.

This is where emerging artificial intelligence (AI) and data-driven tools have the potential to shift the paradigm.

In evacuation analysis, AI-assisted pedestrian modelling can analyse large volumes of historical passenger data to identify congestion patterns, stress-test egress capacity and explore a wider range of behavioural scenarios than traditional modelling alone. Rather than replacing established methods, AI can help fire engineers identify worst-credible conditions more efficiently and to recalibrate safety requirements as precincts grow.

Smoke control design can similarly benefit from AI-based optimisation. Large TOD environments involve countless combinations of fire location, ventilation response and boundary conditions. Machine learning techniques can rapidly screen scenarios to highlight critical cases that warrant detailed computational analysis.

At the precinct scale, AI-enabled data management tools offer a way to track fire safety assumptions across multiple buildings and development stages. As TODs evolve over decades, these systems could flag departures from approved strategies, support version control and reduce the risk of incremental erosion of life safety intent.

Perhaps most importantly, AI opens the door to ongoing operational integration. Predictive maintenance systems can identify failing fire safety equipment before it becomes critical. Digital twins can show what is happening inside a building in real time during an emergency, helping responders make better decisions.

A tool, not a replacement

It is important to be clear about what AI is and is not. AI does not remove the need for conservative assumptions, engineering judgement or regulatory oversight. Its outputs are only as good as the data and logic behind them. Transparency remains essential for approval and accountability.

Used appropriately, AI should be understood as a decision-support tool that enhances existing performance-based frameworks. Responsibility for life safety remains firmly with qualified professionals and authorities.

What This Means for Australian TODs

As Australian cities pursue denser, more interconnected station precincts, fire engineering will increasingly need to operate beyond individual buildings. Lessons from Japan highlight the value of precinct-scale thinking, integrated evacuation planning and smoke management which is tailored to real movement patterns.

AI offers a practical way to support this shift, particularly in large, staged developments where complexity and uncertainty are high. Combined with Australia’s strong regulatory foundation, it has the potential to transform fire safety from static compliance into a continuously managed system.

The future of TOD fire engineering lies not in abandoning established principles, but in expanding their scale, extending their time horizon, and augmenting them with data-driven tools. Done well, this approach can support transport precincts that are not only dense and vibrant, but resilient, adaptable and fundamentally safe.

Authors:

Grant Wang, Fire Safety Engineer at Arup

Hang Zu, Independent Consultant Architect

Peter Johnson, Arup Fellow – Fire Safety Engineering