Function
A rectangular fire damper is used in an air transport system to close off a rectangular air duct in order to prevent fire from spreading through the air transport system. The fire damper contributes to the objective to prevent the propagation of fire to adjacent compartments for a certain time.
Material quality and thicknesses
For normal comfort ventilation, fire dampers are manufactured from the following materials:
- Casing: Sendzimir galvanised steel or Promatect-H;
- Damper: fire retardant and thermally insulating material.
All fire dampers must have a CE marking and be classified according to EN 13501-3.
Other choice of material, depending on the application, in consultation with the supplier.
Connections
The rectangular fire damper has rectangular connections and must be provided with a flange edge according to NEN-EN 1505 or ISO 13351.
Dimensions
The available nominal sizes of the intermediate rectangular fire dampers are standardized according to NEN-EN 1505 (rectangular fire dampers).
They can be chosen as shown in the tables for standard dimensions given in this guide in section 2.1.1.6 (rectangular connections). They refer to the internal dimensions with a tolerance of +0 to -5 mm. The dimensions depend on the manufacture.
Inspection possibilities
It should always be possible to inspect intermediate fire dampers for function and damper position (this can usually be checked from the outside).
Assembly instructions
Rectangular fire dampers must be installed and sealed in accordance with the manufacturer's instructions. The type of wall/floor, the sealing and the type of fire damper determine the classification of the fire damper, including the number of minutes of fire resistance. Sometimes it is not possible in construction to mount the fire damper partially in the fire separation. When the fire damper cannot be installed in the fire separating wall, the duct area between the fire separating wall and the fire damper needs to be insulated in such a way that the quality of the fire separation is maintained. This is carried out under responsibility of the building contractor.
Insulation
The insulation must be installed in accordance with the manufacturer's instructions.
Sustainability aspects
Fire dampers can be connected to air ducts efficiently and make a contribution to the airtightness of the air duct system, if the fittings comply with the airtightness requirements in NEN-EN 1751. Fire dampers that are fitted with a fire resistant surface-mounted clamp do not require additional sealing during installation. This reduces and simplifies the assembly time.
