Position statements are developed by us to inform building development application stakeholders about our position in terms of fire safety, building design and construction and building use. Recognising that there can be occasions where design and construction projects may encounter fire safety issues that are not specifically dealt with under the application of the NCC 2022 or the building assessment provisions, a position statement is considered an approach to convey our advice. Furthermore, the issues may be related to new technology or even commonplace design approaches, that we have determined requires a clarifying statement for designers and assessment managers to understand the underlying issue of fire safety from our perspective.
We have developed position statements for performance solution designs as follows:
- Scope reduction initiative
- NCC fire safety verification method
- Tenability criteria for firefighters
- Fire brigade intervention model
- Use of combustible external cladding
- Use of jet fans in carparks
- Self-storage buildings
- Automated vehicle parking systems (AVPS)
Scope reduction initiative
Building work that meets published scope reduction criteria for a NCC performance solution is not required to be assessed by us to receive our referral agency advice response.
Under Section 57 (1) of the Planning Act 2016, we as a referral agency advice are entitled to provide our referral agency advice response before a proposed building development application is made. We consider that the NCC guides and position statement as published by us may still be relevant for a building development application but referral to us is not necessary as per the scope reduction criteria. Our advice in this case is that the NCC under A2.4 can be complied with where stakeholders apply this Guide as appropriate.
The capacity for firefighters to effectively undertake search and rescue and firefighting depends on the compatibility between the fire hazard, the firefighting equipment provided, and our operational capability. Therefore, our capability to undertake its operations at fire events must be adequate for the fire hazard(s).
NCC fire safety verification method
The fire safety verification method is a performance solution because it sets to achieve NCC compliance by not using the deemed-to-satisfy (DtS) solution. Therefore, the PBDB must be developed for the fire safety verification method, and it should adopt the relevant guidance of the Guide.
The fire safety verification method puts forward a series of scenarios that are informative for assessing the redundancy and sensitivity of a building’s fire safety system that has been modified from the prescriptive requirements.
The scenarios applied in the fire safety verification method should represent the worst fire(s) that are credible in the design life of the building and with respect to operational requirements in the built environment.
The intention of the worst fire assessment and our operational requirements is to establish the assessment method as demonstrating that the building’s fire safety system is ‘fit for purpose’.
As one of the primary purposes of a building’s fire safety system will be to facilitate fire brigade intervention, several assumptions regarding operational requirements and capability are inherently adopted in the method.
However, due to the national approach of the NCC, it cannot anticipate the local operational requirements and capabilities of our specific Regions and for how they may relate to a specific development proposal. Subsequently, the scenarios are incomplete, or at least unconfirmed, in their suitability to be appropriately representative of our operational requirements for the specific building under consideration. Therefore, PBDB is appropriate stage to seek our confirmation on operational requirements and fulfil the mandatory consultation requirements with a Building Approval Officer.
Tenability criteria for firefighters
Tenability criteria are often used to in fire modelling to demonstrate the relative safety and conditions for fire brigade intervention. Scenarios that quantitatively assess the effects of fire in and around a building must report on the circumstances leading to optical density (visibility), temperature or heat flux exceeding 0.1m⁻¹, 120°C and 3kW/m² respectively.
Our firefighters rely on their equipment to operate in environments that would otherwise be untenable for humans. Whilst this equipment enhances the firefighter’s ability to resist the effects of fire, it does not make a firefighter immune to these effects indefinitely.
For example, firefighter personal protective equipment provides a passive layer of protection that permits firefighters to resist higher levels of radiant heat flux and air temperatures for a longer duration than human skin can tolerate, however, eventually the material and circulating air will exceed tenable levels and incapacitate a firefighter.
This duration of an exposure can also be limited by the air supply that firefighters carry with them, requiring them to cease search and rescue and suppression activities and return to clean air environment within their remaining air supply volume.
Certain conditions can also impede or prevent firefighter operations, for example, low visibility during search and rescue.
Fire brigade intervention model
The application of the Fire Brigade Intervention Model to quantify the our activities in the event of a fire emergency at a building must be undertaken in conjunction with input from our Officers.
The Fire Brigade Intervention Model is an available resource to quantify 16 key stages of operational activities, broadly in connection with our arrival, incident assessment, set-up, search and rescue, fire control and fire extinguishment.
This information may be used to justify design aspects of a building’s fire safety system, including the design of firefighting equipment, fire containment and conditions during access, staging, search and rescue and firefighting.
The inputs used for the Fire Brigade Intervention Model will be indicative of the possible scenarios that firefighters may be involved in.
However, it is of paramount importance that the building’s fire safety system is itself capable of satisfying our operational requirements in the built environment if it is to be assumed that we can effectively progress through the 16 stages of operational activities within the Fire Brigade Intervention Model.
Use of combustible external cladding
Combustible external cladding should not compromise safe egress or impede firefighters in undertaking search and rescue or extinguishing the fire using the equipment provided.
Cladding is part of an external wall system of a building. It can be attached to a building’s framework or an intermediate layer of battens or spacers creating air cavities and space for other construction materials like insulation.
Cladding is mainly used to stop wind and rain from entering the building but can also provide sound and additional thermal insulation. Cladding is often used to enhance the building’s facade.
Some types of cladding may contribute to the spread of fire on buildings, and which has resulted in substantial property damage in Australia and multiple fatalities overseas.
Subsequently, the use of combustible cladding on buildings is a fire safety concern for Queenslanders.
The Queensland Government has included Part 11 Division 2 Part 4A to the Building Regulation 2021 and Part 6AA of the Queensland Building and Construction Commission Act 1991 to address those concerns for existing buildings and new buildings respectively.
Necessary for the building development application, is that an application for our referral agency advice response, must be accompanied by certification and Evidence of suitability3 for the performance solution involving combustible external cladding. The performance of the cladding must be assessed against the following criteria:
- Involvement of the combustible cladding in fire does not compromise occupant life safety or prevent the safe evacuation of occupants from the building.
- Involvement of the combustible cladding in fire does not compromise firefighter life safety or firefighting operations with respect to the notification, access, conditions and equipment required by us.
- The combustible cladding does not cause or contribute to vertical fire spread beyond the storey of fire origin.
- The combustible cladding does not cause or contribute to horizontal fire spread beyond the fire compartment of fire origin, or fire spread beyond other fire separating elements of construction.
- The combustible cladding does not contribute to fire spread between buildings on the same site or to adjoining properties.
- The combustible cladding does not produce flaming or falling debris which may result in fire spread to storeys below the storey of fire origin and/or that presents a hazard for egressing building occupants, bystanders, or intervening firefighters.
The information should be provided in addition to satisfaction of our operational requirements in the built environment.
Use of jet fans in carparks
The use of jet fans in a carpark should not contribute to evacuation routes being compromised by smoke or impede the effective operations of a building’s fire safety systems. This position statement and the AFAC guideline Fire Safety for Impulse (Jet) Fans in Car Parks requests designers to consider any proposed jet fan system for its impacts.
To undertake search and rescue and internal firefighting, firefighters require access to trapped/immobile occupants and to areas of the building affected by smoke and fire.
We rely on the evacuation routes within buildings to do this.
Where evacuation routes are incompatible with occupant egress, our access or both, delays and hazards can arise which impede search and rescue and internal firefighting activities.
For example, smoke-logging of evacuation routes and the surrounding areas can delay or impede firefighter access to incapacitated occupants and the fire itself.
This issue is exacerbated where our activities could introduce a path for smoke to travel to the evacuation routes.
Where a ventilation system, such as jet fans force the mixing of smoke instead of forming a stratified smoke layer in the carpark then smoke-logged conditions are likely to happen more quickly.
If the velocity and direction of the exhaust air from a jet fan is enough to displace the fire/smoke plume, this is also likely to cause effects such as ‘skipping’ of sprinkler heads and activations remote from the fire location where the water is needed.
Self-storage buildings
Self-storage buildings can present the case of special hazards for firefighting because the unquantified and uncontrolled storage of items. Our experience is that designers must consider the special hazard cases for these buildings as a general code classification is inadequate and fails to address the specific fire hazards. Therefore, we consider that self-storage buildings should be controlled by active and/or passive fire safety systems to contain the fuel load and the fire intensity.
A fire in a self-storage building can be very large and volatile with serious detrimental impacts on our operational capability to safely access the fire, undertake search and rescue, contain fire spread and extinguish the fire with the equipment provided. Therefore we may advise for special hazards assessment given there are no DtS Provisions under E1D17 and E2D21 and to consider our operational requirements in the built environment. The performance solution design should be for the worst fire(s) that are credible in the design life of the building, particularly with respect to this guide and Table 2 sections: C1 fire resistance, E1 firefighting equipment and E2 smoke hazard management.
To inform our referral agency advice response, stakeholders to a performance solution involving self-storage buildings should provide our Officers with confirmation that:
- there is an enforceable means to restrict the presence of explosive or hazardous substances; and
- there are active and passive provisions to contain the fuel load and fire intensity to a limited size
- the design is within our operational capacity and that of the extinguishing capacity of the equipment provided
- the design prevents the partial, progressive or total collapse of the building and
- the design contains the spread and accumulation of smoke to allow firefighters to undertake search and rescue and extinguish the fire using the equipment provided.
The information should be provided in addition to satisfaction of our operational requirements in the built environment.
Automated vehicle parking systems (AVPS)
The use of automated vehicle parking systems (AVPS), also known as ‘car stackers’, is considered to be a special hazard and outside the scope of the DtS Provisions of the NCC. Car stackers should therefore be addressed as a performance solution.
Performance solutions should be developed with consideration to AFAC Fire Safety Requirements for Automatic Vehicle Parking Systems Guideline and should also satisfy operational requirements in the built environment. The AFAC guideline contains detailed guidance on operational firefighting concerns and the hazards involved in fighting vehicle fires. To assist designers to better understand the importance of providing access and fire safety systems in these buildings, the fire hazards and considerations are included (but are not limited to) the following:
- Accelerated horizontal and vertical fire spread potentially compromising fire brigade intervention times for search, rescue, control and extinguishment activities.
- Rapid development of heat and dense smoke, limiting firefighting operations prior to the onset of firefighter tenability limits.
- Difficulties in applying effective firefighting medium due to shielding of fire by other vehicles; consideration to be given to two access points for firefighters to provide alternative means of attack to shielded fires in a dense storage configuration.
- Shielded fires resulting in the need for firefighters to manually force bonnets, doors, boots, panels etc; risks to firefighters exacerbated due to poor access in a car stacker situation.
- Risks of firefighter injury due to dragging hoses and negotiating around vehicles and other obstructions etc.
- Other hazards e.g., electric hybrid vehicles storage batteries; LPG-fuelled vehicles and BLEVE; failure of vehicle brake systems; fuel fires; failure of the car stacker structure etc.
Note: refer to the AFAC guide for further details/information as this statement is only summarised.
To inform our referral agency advice response, stakeholders to a performance solution involving the use of ‘car stackers’ should provide our Officers with suitable evidence demonstrating that the solution has addressed the AFAC ‘Fire Safety Requirements for Automated Vehicle Parking Systems’ Guideline. This includes consideration of AS 5124 (Safety of machinery - Equipment for power driven parking of motor vehicles etc.), Appendix ZX – Additional Considerations for Australia, in particular ZX5 - Fire Brigade Requirements.
This information should be provided in addition to satisfaction of operational requirements in the built environment.