The main purpose of fire and smoke curtains is to prevent or slow down the ingress of fire and smoke. The curtains should enclose or canalise smoke and/or fire to prevent it from spreading. Most lift doors will not be fire rated and therefore they would need to be protected to maintain the compartmentation of the lift shaft.
Could I just install a smoke curtain?
Simply put, the answer is no. Believe it or not even if smoke curtains are certified to EN 12101-1 they are not tested to provide any form of smoke seal even if they are installed with side guides. The lift opening would need to be protected by a barrier with the same integrity as an S rated fire door so a fire curtain tested to BS EN 1634-3 could be used.
How do fire curtains work?
The curtain fabric would be wound around a steel roller in the curtain head box. When the fire alarm is activated, the system removes the power from the roller motor and the curtain descend under gravity in a controlled manner until the weighted bottom bar lands on the floor to form the seal. The edge of the curtain travels inside steel side guides which again help to form the seal between the curtain and the wall of the opening.
If they come down with no power how can escaping occupants get past?
Emergency egress buttons can be installed on the lift side of the curtain which allow occupants to raise the curtain when required. The system will time out and the curtain will deploy automatically behind them. Easivent use an illuminated push switch which can be seen in low light situations.
Easivent’s illuminated ingress button
What does the builder need to provide to install this type of fire curtain?
The builder needs to provide a suitable opening for the fire curtain and a way of integrating the steel head box and side guides. In public areas the head box is normally hidden behind a cladding façade but in areas such as service corridors the box and guides can be face or reveal fixed. An important consideration in face and reveal fixed installations is that the client would be required to provide physical protection of the head box and guides. This is a requirement of the British Standard found in BS 5824.
Typical example of how to protect side retention guides
The Easivent range of fire curtains are a lightweight option of providing 90 minutes’ fire protection, and with the curtain retracting neatly into a compact steel enclosure they also allow unobstructed access through the protected openings when not in use. Take a look at the range