Will your fire department be able to do it? Does your fire department respond to a hospital, nursing home, school, office building or apartment building that has a standpipe system? Photo by John Newell Figure 1. A pressure-reducing device on a hose outlet. It is...
To access the remainder of this piece of premium content, you must be registered with Firehouse. Already have an account? Login
Register in seconds by connecting with your preferred Social Network.
Complete the registration form.
Will your fire department be able to do it? Does your fire department respond to a hospital, nursing home, school, office building or apartment building that has a standpipe system?
Photo by John Newell
Figure 1. A pressure-reducing device on a hose outlet.
It is important for fire departments to pre-plan and be familiar with standpipe systems in buildings in their response areas. Pay particular attention to locations of siamese connections in relation to nearby hydrants, locations of hose outlets within the building and the presence of pressure-regulating devices at the hose outlets.
Standpipe systems can be identified as wet or dry. A wet standpipe system has water in the riser at all times. A city water main, gravity storage tank, pressure tank or any combination of those may feed a wet standpipe system. The system may also have an automatic or manual fire pump to boost pressure to the upper floors of the building. Either way, the fire department still has to supply the system.
A dry standpipe system does not have water in the riser at all times. Automatic dry standpipes have air pressure in the riser. When a hose outlet valve is opened, the air is released and water is allowed into the system. This type of system is good for areas that may be exposed to freezing temperatures. Manual dry systems do not have water or air pressure in the riser and no water source other than the fire department pumping into the system.
Some standpipe systems have pressure-reducing devices installed at the hose outlet that may reduce or restrict pressure at the hose outlet. Some types may be removed by firefighters before the hose is hooked up to the system. Other types may be opened to allow more flow, and a third type is not removable or adjustable. The third type could be dangerous for firefighters and must be discovered during pre-planning before it is needed at a fire. Every effort must be made at fires to remove or fully open pressure-reducing devices (Figures 1 and 2).
Supplying a Standpipe System
Photo by John Newell
Figure 2. Note that this pressure-reducing device is not fully opened.
Whenever a hoseline is stretched off of a standpipe, the system must be supplied by the fire department with three-inch or larger hose. Some larger buildings have more than one siamese connection. As a rule of thumb, a separate pumper should be hooked up to each siamese to ensure an uninterrupted water supply to the firefighters operating the hoseline. Pump pressure should be 100 psi at the siamese plus 5 psi for each floor above grade.
Standpipe systems may also be supplied by hooking up hose to a first- or second-floor hose outlet. This action may be required if the siamese connection is damaged or has been vandalized. It is a good practice to have a kit for the engine pump operator with the tools and fittings needed to make the hookup (Figures 3 and 4.) Basic items may include:
- 18-inch pipe wrench
- Needlenose pliers
- Double male fitting
- Double female swivel
- Reducer fitting
Photo by John Newell
Figure 3. Pump operator’s bag.
Frozen female swivels, debris clogging the siamese, a broken clapper valve or defective threads are some common problems that may be encountered at the siamese. To overcome these problems, use the following recommendations:
- The frozen female swivels may not turn due to rust or ice. Tap the swivel with a tool to loosen it up or insert a double male fitting then a double female swivel fitting to complete the connection of hose.
- If during the hookup you discover debris in the siamese, use caution – there may be broken glass, garbage or even discarded needles in the siamese. Look closely with a flashlight before reaching in to remove objects. A pair of needlenose pliers may be helpful to remove objects that can be seen.
- A broken clapper valve can be dealt with, if time allows, by quickly stretching a second supply line to the other side of the siamese or by inserting a double male and a cap into the other swivel.
- Defective threads will probably require a supply line stretched to a first- or second-floor hose outlet.