Pressurisation ductwork systems

Pressurisation ductwork is the ductwork used as part of a pressurisation system. Typically used in protected stairways, lobbies, corridors and fire fighting shafts, a pressurisation system is a special form of mechanical ventilation which maintains a positive pressure in critical areas to prevent smoke entering from adjacent areas.

• Pressurisation ducts must be able to maintain an air supply to critical areas for the duration of the fire.
• Air supply must be maintained, fire dampers cannot be used.
• All ductwork penetrating fire compartments must be fire rated in order to maintain compartmentation.

Ductwork ( shown ) a minimum rating of one hour for integrity and insulation to resist fire from outside (Type A).

Ductwork ( shown ) in the final compartment requires a minimum rating of one hour for integrity to resist fire from outside (Type A).

Fans classified to EN 12101-3 must be used.

All fire rated ductwork and penetration seals must be tested BS EN 1366-1 and classified in accordance with BS EN 13501-3 by a recognised NAMAS/UKAS accredited laboratory.

Note: Final approval must always be obtained by the local building control officer/fire department prior to commencement of construction