Standard: According to BS2874
Thread Type: Male BSP
Test Pressure: 24 bar
Size: 3/4" Inlet or 1" Inlet
Note: 1" male inlet is most commonly used
Whilst dormant the vertical pipe work interconnecting the dry riser system to each floor of the building is filled with air. When a pressurized water supply is connected to the inlet breeching the air is forced up the pipe work ahead of the water to the pipe end (roof or top floor level).
This air has to be released to allow water to reach all landing valves on every floor of the building. Without complete removal of all air within the dry riser pipe work fire fighting performance would be severely impaired and water flow may be denied completely on upper levels. Delta Fire’s dry riser air release valve provides the ideal solution to this and any pressurized air is forced out through the air release valve allowing for successful transference of water to all points.
When draining the dry riser system after use the air release valve works in complete reverse allowing an ingress of air facilitating the water's escape. Without the air release valve a vacuum would be created preventing full expulsion of the water.