Fire Damper Separations, EXAPs and DIAPs.. What you need to know

The Field of Direct Application (DIAP) for Fire Dampers can be found in section 13 of EN 1366-2. There is a lot of useful information in regards to Fire Dampers in the DIAP. One section that generates a lot of questions is Section 13.6 Separation Distances.

Section 13.6 states:

A test result obtained for only one fire damper or for two fire dampers with a minimum clear separation of 200 mm is applicable to a minimum separation in practice of:

a) 200 mm between fire dampers installed in separate ducts;
b) 75 mm between fire damper and a construction element (wall/floor) – e.g. for a damper in a wall, this is the distance between the damper casing (largest dimension) mounted in the supporting construction and a wall or floor adjacent to that supporting construction.

Part a) is stating that you need at least 200mm of supporting construction between the dampers installed in separate ducts. You need to check with the manufacturer of the wall system that a section at 200mm is acceptable. If the wall manufacturer states that the smallest section must be 300mm wide in order for them to maintain their certification, then there needs to be 300mm between the dampers.

Please consider that BATT is not regarded as a supporting construction, so installing two dampers that are in separate ducts, in one opening with 200mm of BATT between them would not meet the requirements of Section 13.6 unless it has been specifically tested.

The distance of 200mm can be reduced if the damper manufacturer has specifically tested a reduced separation distance, but the manufacturers installation method must be followed, and one manufacturers tested result cannot be applied to another manufacturers installation methods. Read more "It's Never Just a Fire Test"

In regards to multiple dampers in one opening that are connected to the same duct, and a multiple or battery installation, this is covered by the test method in the Field of Extended Application EN 15882-2.

Section 13.6 in EN 1366-2 does not explicitly reference the separation distance between a damper and another penetration seal (pipe, cable tray, fire door etc.) If you look in Section 13.7 of the latest version EN1366-3 (Fire resistance tests for service installations. Penetration seal), it states: The distance between the aperture edge of a penetration seal and any other penetration (e.g. door) in a building element shall be minimum 200mm. We are of the opinion that other penetration included Fire Dampers.

Fire Dampers can be installed in a opening with other services, provided they have been tested against EN 15882-5 (Extended application of results from resistance tests for service installations. Combined penetration seals). In addition, the ASFP Advisory Note 26 covers Combined Penetration Seals in more detail. As EN 15882-5 is a new standard, little to no primary test data exists at present.

Part b) of Section 13.6 of EN 1366-2 deals with the distance between the damper and the construction edge. For example, this could be from the damper to the slab, or damper to the edge of a wall. The distance as defined by the standard is 75mm, however as before there a couple of things that need to be considered.

The 75mm is the minimum as defined by the standard unless the damper manufacturer has test data supporting a reduced distance. Therefore, a manufacturer could have test data supporting a damper installed 30mm from a construction edge, and this could form part of there certification. As before, just because one manufacturer has achieved a reduced separation distance from a construction edge, you cannot freely apply those rules to other products within that manufacturers range, or dampers made by other manufacturers.

Whilst the standard allows a distance of 75mm (or less if appropriate test data allows it), you need to consider whether it is appropriate and practical on site to have a gap of 75mm. Part b) references that you measure from the damper case (largest dimension) to the construction edge. If the damper has a set of cleats attached, the case that could be 50mm wide, the your actual gap could be reduced down to 25mm. This will potentially cause an issue in trying to fit the nuts and drop rods due to the lack of space. In this case, we would then recommend that you take the 75mm from the edge of the cleat.

Additionally, you need to consider access to the actuator when a damper is close to a construction edge. Whilst it might be possible to install the damper, you need to make sure that you have suitable access to the actuator should there be one fitted. This includes being able to use the key to wind the damper open. If access to the actuator is going to be an issue then the damper and gap can either be increased, or the damper could be rotated so that the actuator is at the bottom. This approach would only be acceptable if the damper manufacturer has appropriate test and certification data that would allow this.

In summary:

The separation distance between dampers installed in separate ducts and between damper and construction edge is covered in EN1366-2.
The distances can be reduced providing there is appropriate test and certification evidence.
Wall manufacturer tested and classified data must be taken into account.
Test laboratories are not construction sites. What can be achieved in a test laboratory might not be achievable on site. When specifying or designing the damper position you must take into account access to be able to install and fit the penetration seal, as per the manufacturer's instruction. If you can’t complete the installation correctly, then your damper installation method will be non-compliant.
Separation distances between dampers and other services is 200mm and is referenced in EN 1366-3.

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Fire Damper Separations, EXAPs and DIAPs.. What you need to know

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