Last edited 26 Jul 2019

Fire damper


[edit] Overview

Fire dampers are devices designed to impede the spread of fire through walls, floors and partitions. The term 'fire damper' is defined by Approved document B, Fire Safety, Volume 2, Buildings other than dwellinghouses, as a:

'Mechanical or intumescent device within a duct or ventilation opening which is operated automatically and is designed to prevent the passage of fire and which is capable of achieving an integrity E classification and/or an ES classification to BS EN13501-3:2005 when tested to BS EN1366-2:1999. Intumescent fire dampers may be tested to ISO 10294-5.'

Fire dampers are installed in the ducts of heating, ventilation and air conditioning systems which penetrate fire-resistant constructions and will automatically close on the detection of heat. Typically, a thermal element will melt and allow springs to close the damper, which will stop the fire from migrating into an adjoining compartment (ref. AMCA 2011).

Smoke dampers are designed to prevent the flow of smoke and products of combustion, and fire and smoke dampers combine both functions. Smoke dampers and combined dampers are generally resettable, and are operated electronically by smoke and fire detectors, as smoke may be present even where temperatures are not elevated.

From 1 July 2013, it became a requirement under the Construction Products Regulation for all new fire and smoke dampers used in UK buildings to be CE-marked to indicate product compliance (ref. CIBSE Journal). This recognises the testing standard BS EN 1366 – Fire resistance tests for service installations, which contains test procedures which ensure dampers are installed appropriately.

[edit] Types of fire dampers

There are three main types of fire dampers:

  • Curtain fire dampers which include a folded curtain held at the top by a thermal element.
  • Intumescent fire dampers which contain elements that expand when heated.
  • Single and multi-blade fire dampers which pivot when released.

Static fire dampers can only be used where ventilation shuts down in the event of a fire. Dynamic fire dampers can resist air pressure where ventilation systems continue to operate.

[edit] Managing the installation

Ensuring effective fire damping requires careful design, specification and installation, with care taken to ensure penetrations are properly formed and dampers are properly sealed. Systems should be inspected and tested regularly and this requires that proper access is provided in the building design.

The principal designer and principal contractor have a role in ensuring the proper design and installation of fire dampers, and installations will be subject to approval under the Building Regulations.

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[edit] External references