Industry puts car park fire safety in the spotlight
A review of the Australian National Construction Code (NCC) Volume One to modernise and improve the fire safety of car parks is underway, instigated by the Australian Building Codes Board. As highlighted by the recently published new guidance, Car Park Design, by the UK’s Institution of Structural Engineers, the design, construction, maintenance, and reuse of car parks needs careful consideration given their purpose is changing from just parking cars to recharging and storing them, alongside lithium-ion battery powered e-bikes and e-scooters, too. These evolving uses and new technologies all impact fire safety of the structure and the safety of occupants located in and adjacent to these buildings.
Multi-storey car park structures are already at dangerous load bearing limits due to the significant increase in SUVs and utility vehicles being used by general drivers. This is compounded by more electric vehicles being introduced to the load risk, including the issue of potential fires as well as overladen structures including load-bearing beams and columns being impacted by ultra-high temperature fires.
As identified by Warrington Fire, considering the rapid uptake of EVs including requirements in the NCC 2022 for the provision of EV chargers to be installed in new buildings, there is a lack of regulatory guidance to address the associated fire safety concerns. At a webinar last year, Warrington Fire shared research into the fire characteristics of EVs with lithium-ion batteries and the implications of these characteristics within the built environment in areas such as car parks. This included insights regarding lithium-ion battery technology and thermal runaway, the impact of charging on the likelihood of an EV fire, the explosion hazard that can be created by the high volumes of combustible gas that may be released from lithium-ion batteries and the effectiveness of available suppression mediums for EV fires.
What are the proposed NCC changes?
The considered changes include sprinkler protection in all car parks with more than 40 cars, removal of the Fire Resistance Level concessions for some open-deck car parks, and sprinkler protected car parks in certain buildings.
The need for change
Importantly, these changes aim to address the fire-related risks associated with modern car parks, such as increased vehicle size, increased fuel load and use of plastic material, new energy sources, and vehicle parking and storage methods.
The current NCC Deemed-to-Satisfy (DTS) provisions are based on research undertaken in the 1980s, underpinning the concession for open-deck car parks with more than 40 cars to not require a sprinkler system. That research also formed NCC concessions for sprinkler protected open-deck car parks reducing fire ratings, providing an allowance for bare steel elements. These guidelines have enabled the construction of numerous, typically commercial, steel car park structures throughout Australia, but a lot has changed since then.
Looking ahead
Since the implementation of concessions by the NCC, the design of vehicles has significantly evolved. Fuel load within modern vehicles has grown considerably, mainly due to the increased use of plastics. New technologies, such as electric car batteries, hydrogen powered cars, and car stackers have also been introduced.
In addition, basement car parks are more frequently used to store goods and often co-located with end of trip change facilities for tenants, accommodating those who cycle, jog or walk to work, further shifting the risk profile of car parks.
The NCC 2025 draft prohibits using ‘expert judgment’ alone to assess performance solutions related to fire safety and structural integrity. This ensures compliance relies on clear methods, evidence, and documentation as changes are defined.
Wormald is working closely with regulators, fire brigades and car park owner operators to mitigate the highlighted risks, including advising on the best way to protect parking structures of all kinds via automatic sprinkler systems for new and existing buildings. For further information on Wormald fire protection solutions, email sales@wormald.com.au.
