Basement Lobbies

Once a basement level is larger than 900m² or deeper than 10m below ground level there is generally a requirement to provide smoke control within lobbies. This is generally (but not always) headed as Facilities for the fire service and is referred to as a “Fire Fighting Shaft”, or is indicated by a “Fire Fighting Lift”, or even just a “Dry Riser/Wet riser, Fire main” The area of concern for ventilation is the lobby containing the rising water main, whether charged or not, that leads directly to the stairs.
If a natural ventilation duct can offer permanent ventilation it should measure 0.4m² free area. (1m x 0.4m)

PSB can save space by offering a mechanical using our own Fire rated extract fans and control panels.