Fire closures

Fire closures of multi-blade design may be accepted provided they meet at least the following
design criteria:
 The fire closure shall consist of not more than 5 single plates, whereas the clear height of each plate
should be at least 20 % of the total clear height of the damper but not less than 200 mm.
 Each damper plate should have an overlap of at least 5 % of its height.
 A circumferential resting bar should be provided.
 Each damper plate should have a thickness depending on its cross section as specified in Table 1.2.
 The construction should be of robust design to avoid vibrations.
Prior to installation, drawings showing construction details of the multi blade fire closure have to be submitted
for approval. The construction is to be tested to the satisfaction of a GL Surveyor.
Special attention shall be paid to a regular service of the multi-blade fire closures.