Fire scenario · cause-and-effect matrix
Fire scenario and cause-and-effect matrix
A fire scenario defines how the building responds to a fire: which systems start in a given zone, in what order and with what effect on evacuation and firefighting. We prepare it for buildings where a dozen or more installations have to act as one.
Basis
When is a fire scenario required?
In the UK and the Middle East this logic usually sits in the fire strategy and its cause-and-effect matrix. In Poland it is a formal document: a fire scenario is required for every building that must have a fire detection and alarm system. The regulations on fire safety design review (Regulation of the Minister of the Interior and Administration of 5 August 2023) require it to be developed jointly by the designer and the certified fire safety expert (rzeczoznawca). The fire safety systems specified in the design must follow from the regulations and from the adopted scenarios.
A fire scenario is a description of the sequence of possible events during a fire that is representative of its location, in particular of a fire compartment or smoke zone. It covers the operation and interaction of fire safety systems, building services and process equipment, and the management measures needed for them to work properly.
Scope
What do the scenario and the matrix contain?
- building description: fire compartments, smoke zones, occupancy risk categories, fire load density
- event description for each zone: fire location, means of detection, stage 1 and stage 2 alarm
- operation of fire safety systems: fire detection and alarm, voice alarm, smoke extraction, pressurisation, fire dampers, fire doors and shutters, sprinklers
- interfaces with building services: general ventilation, lifts, access control, power supply, fire-fighter’s power cut-off switch
- control timing and sequence, failure modes and system behaviour on loss of power
- management measures: role of security staff, control room, phased evacuation, fire and rescue service operations
- the cause-and-effect matrix as an unambiguous table: input event and the response of every device
Complex buildings
Which buildings do we prepare scenarios for?
We specialise in buildings where a simple “fire alarm starts smoke extraction” is not enough. We have worked on metro infrastructure, the Świna tunnel, PGE Narodowy (the National Stadium in Warsaw), Tauron Arena and dozens of multi-storey car parks.
Metro and tunnels
Stations, cross-passages and road tunnels, where smoke control, zoning and evacuation run in one multi-scenario algorithm.
Shopping centres and mixed-use
Malls, retail areas, cinemas and car parks under one roof. Dozens of smoke zones and several smoke control systems at once.
Hospitals and hotels
Phased evacuation, people with reduced mobility, refuge areas and systems that have to run for longer periods.
Stadiums and arenas
Thousands of people, large volumes, smoke extraction from the auditorium and communication with event security.
High-rise and tall buildings
Stair pressurisation, firefighting lifts, zoned evacuation and coordination with the BMS.
Multi-storey car parks
Jet fan and ducted ventilation, smoke zones, electric vehicle charging. We verify the scenario with CFD simulation.
Process
Who prepares the scenario and how does the work run?
- 1
Design review
We review the architectural and MEP design, the zoning, the systems and the evacuation assumptions.
- 2
Fire strategy
We define the design fire events for each zone and how the building responds to a fire.
- 3
Engineering verification
Where smoke control performance or evacuation time is decisive, we confirm the assumptions with CFD simulation and evacuation analysis.
- 4
Scenario and matrix
We write the scenario narrative and the cause-and-effect matrix in a form ready for the system designers and the integrator.
- 5
Commissioning and tests
At handover we check that the systems operate according to the scenario, including with hot smoke tests.
We combine the scenario with CFD simulations, evacuation analysis and hot smoke tests. Where the design departs from prescriptive rules we also prepare a fire engineered solution.
FAQ
Frequently asked questions
Is a fire scenario mandatory?
In Poland, yes, for buildings required to have a fire detection and alarm system. The regulations on fire safety design review require a fire scenario to be developed jointly by the designer and the certified fire safety expert (rzeczoznawca), and the selection of fire safety systems must follow from the adopted scenarios. In other jurisdictions the same content is typically part of the fire strategy and its cause-and-effect matrix.
Who prepares the fire scenario?
In Poland the scenario is prepared jointly by the designer and the certified fire safety expert at the building permit design stage. At F&K it is developed by our team of certified experts and fire safety engineers, and we confirm the smoke control and evacuation assumptions with calculations and simulations.
What is the difference between a fire scenario and a cause-and-effect matrix?
The scenario describes the fire and the building’s response in words: what happens, in what order and why. The cause-and-effect matrix is the same logic written as a table, ready for programming the control panels and checking at commissioning. A large building needs both documents.
When should a fire scenario be commissioned?
Ideally at the building permit design stage, before the disciplines select their equipment. A scenario drawn up after the fact forces changes to installations and delays handover. In complex buildings we update it at the technical design stage and before the acceptance tests.
How much does a fire scenario cost?
The cost depends on the number of fire compartments and smoke zones, the number of systems and whether CFD verification is needed. We quote individually after reviewing the design.
Designing a complex building?
Send us the design or a project description. We will define the scope of the scenario, the analyses needed and the timeline.