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Classification of Fire Rated Ductwork

BS EN 13501-4: 2007 Fire classification of construction products and building elements Part 4: Classification using data from fire resistance tests on components of smoke control systems (Part 3 for non-smoke).

The aim of the classification report is to provide a designated way of presenting the classification of a product, based on results obtained during EN fire tests.

Typical Classification specified for Smoke Control system ducts (Multi-Compartment)

E I 120 ( i <-> o ) Ho Ve S
Integrity Insulation Time in minutes tested for fire inside duct tested for fire outside duct tested for horizontal duct tested for vertical duct tested for smoke leakage

The classification above is completed by the addition of the following if applicable:

Multi=Multi Compartment
Single=Single Compartment
E300=300°C smoke temp single compartment only
E600=600°C smoke temp single compartment only
EXAP 2500mm x 1250mm= EXAP size of Duct tested to BS EN 15882-1

S - When added indicates a leakage rate of less than 5m3 per m2 per hour. 500Pa, 1000Pa, or 1500Pa indicates that when tested at these negative pressures the Duct is suitable for use up to that tested negative pressure and also up to a positive pressure of 500Pa.

The classification shall indicate if the performance criteria are satisfied by fire from inside or fire from outside or both and whether it applies to vertical or horizontal orientations or both.

For example, a classification EI 30 (VeHo i<>o) indicates a Ventilation Duct capable of satisfying 30 minutes integrity and insulation from both inside to outside and vice versa in both vertical and horizontal applications.