Passive fire protection is the prevention or delay of the spread of fire and/or smoke to different parts of the building by using construction elements designed with this purpose.
Passive (as opposed to active) Fire Protection uses structural systems that don’t rely on activation from technology or human intervention and do not require water or power for it to perform. This protection is supported by good fire safety management and using tested Passive Fire protection systems. This confirms that fire protection is available at all times, which facilitates escape in the event of a fire and prevents damage to adjacent buildings.
Passive fire protection has established performance criteria, verified by test data and it must be correctly specified, installed and maintained.
What are the goals of Passive Fire Protection?
The Goals of Passive Fire Protection are:
· Protection of life – people can evacuate safely
· Protection of property – the less the fire burns in a building means fewer items to repair
· Continuity of business operations – If part of the building is still operational, the business can continue to operate with limited resources.
Passive Fire Protection compartmentalises a building or part of by using fire-resistance-rated walls and floors, which controls and prevents the fire from spreading quickly throughout the building and provide time for occupants to escape safely.
Compartments have vertical (walls) or horizontal (ceilings/floors) elements and are usually penetrated by services such as electrical cables, cable trays, metal and plastic pipes, ducts, and air conditioning systems. All penetrations need to be fire stopped to maintain the fire-resistance rating of these walls and floor.
How does it happen?
Two fundamental aspects of passive fire protection are:
Resistance to fire – mainly concerned with the ability of a substrate (such as a wall or floor/ceiling) to limit fire spread, including passage of fire products through it, or to prevent collapse in the case of a loadbearing element. For example, a fire sealant will seal the gaps and stop the passage of the fire.
Reaction to fire – mainly concerned with the surface burning behaviour of an element or material and the extent to which it promotes rapid flame spread or smoke production. For example, a plastic pipe usually rapidly melts and will leave a hole on the substrate. A fire collar is used on this type of penetration, and the reactant material will expand and quickly close this hole.
Passive fire protection is a key part of the fire safety features in a building. It should be subjected to the same rigorous installation documentation, inspection and sign-off as active fire protection. Also, passive fire protection systems should be installed in strict accordance with the consented plans (if identified explicitly in them) or the manufacturer’s specifications.
Check our article on "Who is responsible for the passive fire protection in a building".