Wet rising mains are for use by the fire brigade or other trained personnel. They are installed into new buildings above 50 metres, or in cases where it is difficult to provide a suitable breeching inlet position to a dry riser.
UK Sprinklers Ltd specialises in the design, install, testing and commissioning of wet riser systems in accordance with BS 9990:2015. In order to meet this standard, the minimum outlet pressure required at each wet riser valve is 8 bars. Due to the height of the building and the pressures used, pressure regulating valves (PRVs) are fitted to the outlets at each floor.
In addition, a permanent means of testing needs to be provided. This is usually done by performing a test drain which discharges either to a drain, sump or returned to the wet riser tank.