Dry risers are systems added to tall buildings that help firefighters tackle fires without dragging heavy hoses upstairs.
Fighting a fire at ground level is relatively straightforward. But combating one in a tall building with ten floors or more is significantly more challenging.
For this reason, many buildings have dry risers. These systems let firefighters tackle fires on each floor, helping to put out the blaze faster and stop it from spreading.
What Are Dry Risers?
A dry riser is a pipe that runs vertically up a building, supplying water for firefighting purposes on each floor. There is an inlet on the ground floor where firefighters can pump water higher in the building and then subsequent outlets on each floor to fight fires directly.
Architects usually locate outlets or “landing valves” inside dry riser cabinets on each floor, close to firefighting shafts. Cabinets are often red and come with signs and notices informing the public that they are for firefighting purposes. “Dry Riser” labels on the outside tell the public and non-professionals what they are.
How Do Dry Risers Work?
Operating dry risers is straightforward. If a building is on fire and rescue workers need to supply water higher up, they connect the fire engine hose to the inlet on the ground floor and then pump water through it at high pressure so that it can supply water further up the building.
Firefighters inside the building locate the dry riser cabinet, open it, and attach another hose to the outlet. Wearing personal protective equipment, they can direct water from below to the areas of the building that need it most.
Such systems are easier for firefighters to use because they let them carry much shorter hoses. Conventional hoses are heavy but those connected to dry risers are lighter and easier to manage. Firefighters can work more efficiently using them.
To be compliant with the law, British dry risers need to abide by various standards, including:
- BS9990:2015
- BS9991
- BS9999
- Approved Document B (Fire Safety) of the Building Regulations (England & Wales)
The person who owns the building is responsible for following these regulations. Landlords, for instance, should perform visual tests every six months to ensure that their dry risers are in good condition and fit for purpose.
When Do Fire-Fighters Need To Use Dry Risers?
Nowadays, dry risers are an integral part of building design, something architects incorporate from the outset. Building regulations state that when the distance between the entrance and the top floor is more than 18 metres, a dry riser is essential. Architects should also include them if floors extend more than 10 metres below the ground.
Dry risers are necessary because they can save lives. If firefighters can get a blaze under control higher up in a building, evacuating occupants is easier.
However, not all buildings have dry risers installed as standard, meaning that they could be breaking the law.
If your building requires dry riser installation, always consult with experts. They can perform the installation to the correct specification.