How do fire doors work?
Fire doors can help to stop fires from spreading through a building, giving people more time to escape and helping to ensure there are safe exit routes. This also gives the fire emergency services more time to reach the building and work to extinguish the flames before the fire spreads.
Fire doors work by creating a barrier, stopping the fire and toxic smoke spreading uncontrollably through a building. They can withstand fires due three unique aspects: construction materials, sealing mechanisms and fire resistance ratings.
1. Construction materials
Fire doors, unlike regular doors, are made with specialised materials which have undergone a rigorous manufacturing process to ensure they are fire resistant. They are made with:
- Fire-resistant glass: fire doors with windows will befitted with glass panels which have fire-resistant coatings
- Solid wood or steel: to provide strength and durability, a fire door’s core material will be solid wood or steel
- Fire-rated hardware: hinges, locks and any other hardware must all be made from a fire-rated material
2. Sealing mechanisms
Ensuring fire doors can effectively contain a fire, with various seals, is a key part of what helps stop the spread of a fire. The most common mechanisms are:
- Threshold seals: installed at the bottom of the door, these help to reduce the risk of the fire and smoke escaping under the door in the gap between the door and the floor
- Intumescent strips: to create a tight seal around the edges of the door, these strips expand when exposed to heat and prevent fire and smoke passing through
- Smoke seals: to reduce the flow of smoke through gaps, smoke seals help to contain flames and improve visibility during evacuation
3. Fire door ratings
Fire doors are given ratings to indicate how long they can withstand a fire, as different types of doors are more effective than others. Depending on the type of building, regulations may require doors to meet a particular rating. The most common ratings are:
- FD30 – can withstand a fire for up to 30 minutes
- FD60 – can withstand a fire for up to 60 minutes
- FD90 – can withstand a fire for up to 90 minutes
- FD120 – can withstand a fire for up to 120 minutes
If a fire door is altered in any way – for example: the seals are painted over, it is drilled or cut into, or the hardware is replaced –the fire door will no longer meet the regulations and its effectiveness will be compromised. Any changes should always be made by a qualified individual.
What are the legal requirements for fire doors?
Fire doors are a legal requirement for various types of building, you can find out more here.
Additionally, it is important fire doors are inspected regularly to ensure they are maintained properly and continue to be effective and, according to the Regulatory Reform (Fire Safety) Order 2005, a nominated responsible person must ensure these inspections are undertaken when legally required. Find out how often your fire doors must be inspected here.
If you are responsible for ensuring your building’s fire safety is up to scratch, please get in touch and our experts can arrange for your fire doors to be rigorously inspected, to ensure they meet the regulations.
