Glossary — Passive Fire Protection
Fire Curtain
A fire curtain is a motorised, fabric-based barrier that descends automatically on fire alarm activation to form a fire-resisting compartment boundary across a large opening. Classified to BS EN 16034, fire curtains provide passive fire protection in atriums, shopping centres, theatres, and open-plan buildings where solid fire walls are not architecturally practical.
Classification
Fire curtains are classified under BS EN 16034 using letter codes: E = fire integrity (time in minutes — e.g. E 30, E 60); Sa = smoke control at ambient temperature; Sm = smoke control at elevated temperature (200°C); C = closing reliability class. A curtain rated E 30 Sa C4 provides 30 minutes fire integrity, ambient smoke control, and closing reliability class 4.
Fire curtain types and applications
| Type | Purpose | Rating | Typical application |
|---|---|---|---|
| Boundary fire curtain | Creates a fire-resisting compartment wall across a large opening (atrium, concourse) | E 30, E 60 (integrity only) | Shopping centres, office atriums |
| Smoke curtain (fire-rated) | Channels smoke to extract points; also provides limited fire resistance | Sa (smoke control at ambient), Sm (smoke control at 200°C) | Car parks, atriums, corridors |
| Stage safety curtain | Separates stage from auditorium to contain fire and allow audience evacuation | E 30 min; BS 7036 / ABTT guidance | Theatres, concert halls, lecture theatres |
| Horizontal fire curtain (floor curtain) | Closes off atrium voids floor-by-floor to prevent vertical fire spread | E 30 or E 60 | Multi-storey atriums, escalator voids |
Fire curtains and compartmentation strategy
Fire curtains allow architects to maintain open, connected spaces that would otherwise require fire-rated walls and doors to achieve fire compartmentation. In an atrium building, a horizontal fire curtain at each floor level can prevent vertical fire spread up the void. In a shopping centre, boundary curtains can divide mall areas from anchor stores without permanent walls.
Fire curtains must be considered alongside the building's smoke control strategy. In many buildings, smoke curtains and mechanical smoke extraction work together — the curtains channel smoke to extract points while the mechanical system removes it. See our smoke control system glossary entry for the full framework.
Life safety features
All fire curtains used in occupied spaces must incorporate:
- Obstruction detection sensor — stops or reverses descent on contact
- Controlled descent speed — slow enough for persons to move clear
- Manual override at control panel
- Battery backup — minimum 72 hours standby, sufficient for full operation
- Indicator lights showing curtain status (deployed / retracted)
Interaction with escape routes
Fire curtains must not obstruct means of escape. Where a fire curtain deploys across an escape route, a manual override within reach of the curtain and a clear alternative escape route must be provided. The fire strategy must demonstrate that escape can be completed safely before any curtain descends to a position that restricts exit.
Frequently asked questions
FAQ