Technical Booklet E Fire Safety·Page 123·4.44
Ventilation ducts penetrating fire separating elements
Ventilation and air conditioning ducts passing through fire separating elements must maintain fire resistance using appropriate methods and fire dampers tested and classified to specific standards with minimum 60-minute E or ES classifications.
Where a ventilation or air conditioning duct passes through a fire separating element it should comply with an appropriate method for maintaining the fire resistance of the wall, floor or barrier given in BS 5588-9 the relevant recommendations of BS 9999.
Fire dampers should be tested to BS EN 1366-2 and be classified to BS EN 13501-3. They should have an E classification not less than 60 minutes. Fire and smoke dampers should also be tested to BS EN 1366-2 and be classified to BS EN 13501-3. They should have an ES classification not less than 60 minutes.
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