By Thomas N. Warren
Recently, I observed a building fire in a suburban neighboring town. I happened to arrive as the first-due engine was approaching and stopped to watch the fire operation in a two-story, mixed-use structure. There was a hydrant at the entrance of the parking lot and the building was approximately 100 feet from the hydrant. There was smoke showing from the second floor on the B/C sides. The first-due engine parked on the B/C corner, and a handline was stretched to a stairway leading to a second floor canopied walkway/balcony across the entire length of the C side of the building. A second-arriving engine picked up the hydrant and laid a supply line to the first-arriving engine company, then stretched a second handline up the same stairs as the first handline. A short time later, a chief arrived and assumed command of the operation. There was no ladder company on scene, and when the third engine company arrived it parked near the other two engine companies. Being a small suburban combination department, this meant that there were limited personnel available and they made good use of the resources they had on scene. Before long they had the fire under control.
The fire operation went well and looked very well-coordinated with one exception–there was a fire department connection (FDC) on the side B of the building that went unused. There was no visible fire from outside the building, but there was a lot of smoke, most likely due to the activation of a sprinkler system. The first-due engine company parked their truck next to the FDC and never connected any hoselines to the FDC to feed the sprinkler system. I thought that maybe the pump operator felt that firefighters could knock down this fire quickly and did not need to connect any lines to the FDC to supplement the sprinkler system, or perhaps he was concerned about leaving the pump panel.
I relayed this story to some of my colleagues, who insisted that this happens often in areas where fire departments do not encounter private fire protection equipment on a regular basis. They simply focus on advancing hoselines because the occurrences of FDCs are not all that common and, in some cases, they may not be sure of what happens when they connect to them or how to pump to them. Coming from an urban fire department where we search out FDCs and include them in our standard operating procedures and fireground operations gave me some pause, and the more I reflected on it, the more I realized that what I always viewed as routine operations for me may be foreign to some young firefighters in rural or suburban areas.
There are many fine textbooks and articles written about sprinkler systems and standpipe operations, but I would like to focus on the FDC itself and how to incorporate it into fireground operations. The complexities and operational issues of standpipe systems and sprinkler systems warrant further study independent of this article.
The FDC can be found anywhere in the country. They are considered as fire protection equipment that is part of individual buildings: privately owned, privately maintained, and installed to specific National Fire Protection Association codes. The FDC can be found in modern buildings and in very old buildings alike. The FDC will present as highly polished chrome, brass, or painted (usually red) devices attached to the outside of a building or remote from the building. FDCs are part of a sprinkler or standpipe system that insurance companies began to require to limit their losses.
The primary function of an FDC is to receive water from a fire department pumper and introduce that water to a sprinkler or standpipe system and supplement the water supply to that sprinkler or standpipe system. One of the primary goals of every fire department suppression operation is to supply and maintain an adequate water supply and adequate pressure. To achieve this fundamental need, fire department engine companies will obtain a water supply to their truck and then connect and pump into the FDC. When engaged in a fire suppression operation, the incident commander should ensure that fire department pumpers connect to all available FDCs to ensure that adequate water and pressure is provided to the sprinkler or standpipe system. This can be a very valuable tactic if there are closed sectional valves somewhere in the system, if the fire is in an area not protected by a particular FDC connection, or if a fire has caused many sprinkler heads to activate.
FDCs for standpipe systems and sprinkler systems can look very similar and, in most cases, are identical in appearance. As stated earlier, the FDC will present as highly polished chrome, brass, or painted (usually red) siamese device that is attached to the outside of a building or can also be remote from the building (lawns, parking lots, or roadways). Every FDC is required to have markings or signage that indicates what type of system the FDC supplies. These markings or signage will clearly indicate “SPRINKLER SYSTEM,” “STANDPIPE SYSTEM,” SPRINKLER AND STANDPIPE,” and will also indicate if the FDC only serves a portion of the building. Traditional FDCs are essentially a siamese device designed with two female 2 ½-inch intake swivel connections and have either one or two clapper valves just inside the swivel connections. The clapper valve is designed to prevent the back flow of water out of the FDC during firefighting operations. The swivel connections will have caps to protect the swivel connection and prevent any debris from entering the FDC itself. The caps can be either a metal breakaway cap, screw in male cap, plastic break-away cap, or a locking cap. The breakaway type caps are removed by striking the center of the cap with any hand tool such as a hydrant wrench. With the increase popularity of Large Diameter Hose (LDH), FDCs can be found in some areas with a 4- or 5-inch stortz connection instead of the traditional 2 ½-inch siamese connections. All markings and signage will remain the same for these LDH stortz connections. In some rare cases, a single 2 ½-inch FDC connection may be found. and this too must be properly identified with signage or labeling.
FDCs are usually extremely reliable, but there are some common problems associated with them. Many times debris can be found inside the FDC female connection, particularly when the FDC caps are missing. Firefighters should never place their fingers inside the FDC, but rather clear the debris with a spanner wrench. There have been cases where hypodermic needles have been found inside FDCs. Another problem found on FDCs is that the swivel female connection does not spin as designed. This can occur when the swivel has been painted and repainted many times over many years or when the female swivel has been struck and damaged by truck or other vehicle. When an engine company is faced with this type of problem, the pump operator can insert a double 2 ½-inch male adapter to the FDC then attach a 2 ½-inch double female adapter to the double male to make the hose connection. If the FDC is so badly damaged, another option is to connect a 3-inch feeder line to the first floor standpipe discharge outlet (if available) and pump into the system through the standpipe discharge. This technique can also be used to increase water volume or pressure. Always check for the presence of gaskets in the 2 ½-inch female connections and carry spare gaskets on your apparatus. Spare 2 ½-inch male caps can also be useful in the event it becomes necessary to cap a malfunctioning clapper valve. Be mindful that most sprinkler and standpipe systems will have a 2 ½-inch test discharge connection for fire pumps. If you encounter a 2 ½-inch connection with a male thread, it is not an FDC but rather a fire pump test discharge. In many cases there will be several test discharge connections grouped together.
Pumping into an FDC is very straightforward. The first thing necessary is to secure a reliable water supply for your pump and then connect either two 3-inch feeder lines to the FDC or a single LDH line to the FDC. All pumpers will pump their capacity at 150 psi at the pump, so increase the throttle slowly until your discharge pressure is at 150 psi while being careful not to run away from your water supply. If your pumper is equipped with a multi stage pump, place the pump in the volume stage. As an engine company pump operator, this is always a good place to start your pumping operations before performing any complicated hydraulic calculations. For a more precise calculation, allow 5 psi friction loss per floor and add another 25 psi for the friction loss in the sprinkler or standpipe system itself. Standpipe operations will require additional friction for the hose used on the fire floor. The ideal position of the apparatus should be as close to the hydrant (water supply) as possible and no more that 100 feet from the FDC. In most cases, the conditions on the fireground will dictate where your apparatus will be placed.
Firefighters should familiarize themselves with all the buildings in their district. Note where the FDCs are located, what systems they serve, and the location of the closest water supply. The next step is to incorporate this knowledge into every response, making the FDC a common part of every response and preplan. Don’t be afraid to get out of your truck and spin the couplings; look for a close hydrant and access points. FDCs are there to make your life easier, so don’t forget to use them.
Thomas N. Warren has more than 40 years of experience in the fire service in both career and volunteer departments. He retired as assistant chief of department of the Providence (RI) Fire Department after 33 years of service. Presently he is a faculty member at Bristol Community College in the Fire Science Technology Program teaching a variety of subjects in the fire science discipline. He holds a Bachelor’s Degree in fire science from Providence College, an Associate’s Degree in business administration from the Community College of Rhode Island and a Certificate in Occupational Safety and Health from Roger Williams University.
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