What is a dry riser?
A dry riser is a vertical pipe in a building, empty in normal conditions, that firefighters charge with water from a pumping appliance at ground level and use at outlets on upper floors.
It exists so a hose does not have to be run up a stair. That saves the time and the obstruction of laying hose through the escape route people may still be using.
It is firefighting equipment rather than occupant equipment, which is why the outlets are in protected stairs or lobbies and why the inlet is where an appliance can reach it.
Its failure modes are all about access and integrity: a blocked inlet, a missing cap, a vandalised outlet or a valve that will not open. None of these are visible from anywhere an occupant goes.
In practice
An inlet box with a missing cap and a cracked coupling.
It is at street level, it has been vandalised, and it has been that way long enough that nobody notices it.
A dry riser is equipment the fire and rescue service rely on arriving to find serviceable, and its condition is invisible to the building's own occupants.
Testing is a specialist activity and the visual condition of the inlet is not.
What goes wrong in practice
- Inlet obstructed by parking, bins or landscaping added after handover.
- Outlet cabinets vandalised or used as storage.
- Testing recorded for the building as a whole with no identification of which risers were tested.