Following on from our previous blog covering specifying fire curtains, we now turn to automatic controls for smoke and fire curtains.
Again we’ve been seeing lots of long-winded specifications calling for quite sophisticated control functions and features, mentioning potentially confusing features such as ‘epicyclic gearbox retarders’ which seem to be very specific to certain manufacturers rather than being an application or project requirement. These kinds of specifications may well be over complicating matters and potentially could build in reliability issues as well as increasing capital and maintenance costs unnecessarily.
Smoke and fire curtains: what they do. Keeping things simple, smoke and fire curtains drop a piece of weighted fabric (either partially or fully) from a roller in an emergency either to provide a barrier against smoke flow (in the case of smoke curtains) or maintain fire compartmentation (in the case of fire curtains).
Uninterruptible power supplies: not essential to fire operation. With both smoke and fire curtains there is normally a zone control panel (to control an individual curtain or a group of curtains) and a local battery back-up (BBU) or a uninterruptible power supply (UPS). A BBU or UPS is mainly to prevent nuisance dropping of the curtain, for example in case of a loss of mains power. To be clear a BBU or UPS is not essential in terms of fire operation because the curtains will fall automatically under gravity when the power is lost.
The exceptions to the rule. However in certain circumstances we will need a BBU or UPS to be sure the curtain will deploy as designed in a fire condition. That’s when, for example, we need to use a drive-up, drive-down smoke curtain, for use when multiple or intermediate potential drop positions are required, perhaps where curtains are located in escape routes.
A BBU or UPS will also be needed when a drive-up, drive-down fire curtain is required, for use when we have emergency access or egress controls which enable the curtain to be raised after it has been lowered, either in order to allow people to escape under it or to let fire fighters through.
However from what we see these applications tend to be the exception rather than the rule.
Keep things simple: focus on the actual requirements! Curtains which drop under gravity are inherently reliable and perfectly suitable for the vast majority of applications, so in order to keep things simple and costs down it pays to give consideration to the actual requirements of the project when specifying control systems for smoke and fire curtains.
Keep an eye out for forthcoming curtain blogs where we’ll be discussing other control features, or use our tag cloud to search for previous articles.
Join Paul Compton, Technical Director at Colt UK, from 12.30-13.30 GMT on Friday 27th February 2015, as he presents a free CPD webinar on the design considerations when integrating smoke and fire curtains into a building.
Fire curtains seal off an area which is on fire, thereby preventing fire from moving from one area to another. Smoke curtains prevent the passage of smoke.
In this seminar we cover:
- The differences between smoke and fire curtains.
- The standards which each type of system has to comply with.
- The design aspects to consider when integrating these systems into a building
The webinar is fully CPD-accredited, which will enable you to claim CPD points. There is ample time allowed for questions and answers at the end of the formal part of the webinar.
Paul Compton is Technical Director for Colt, experienced in smoke control, HVAC, solar shading and louvre systems.