P2 ~ Sprinklers Made Simple

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Valves

All fire service control valves must be indicating valves-i.e., just by looking at them you can see whether they are open or closed.

Outside stem and yoke (OS&Y). The amount of stem showing should be the same as the depth of the valve body-i.e., six inches of valve, six inches of stem. When the stem is out, it’s open. The red box is a tamper switch that will send a signal to the panel if someone tries to maliciously shut the valve. The lock and chain shown here are an insurance requirement, not code (photo 6).

Post indicator valve (PIV). This valve is found outside buildings and has a window that will indicate OPEN or SHUT. A wrench sits on the operating nut as it does on a hydrant and can be locked on the side. Both PIVs shown are also electronically supervised with tamper switches (photo 7).

Wall PIV. Found on the outside wall of a commercial building, similar to the PIV, it has a window indicating OPEN or SHUT. On the inside of the wall attached to this valve is a large fork that spears the operating valve on the riser so you can operate the riser valve from the outside of the building. The valve shown has a tamper switch on it as well (photo 8).

Indicating butterfly valve (IBV). This valve is found on the riser usually for smaller piped systems. Larger risers require larger valves and operating handles. The indicator is the yellow bar in the center of the valve. As it opens and closes, the bar rotates. Since sprinkler valves must be indicator valves, an open valve will show the bar in line with the pipe. This one is open (photo 9).

Sprinkler Heads

Sprinkler heads come in various sizes, configurations, and temperatures. All have a specific purpose and use. One size does not fit all!

Upright. This sits on top of the pipe and is usually found in dry systems so that when the system drains down after tripping, the water doesn’t remain in the heads and pipe nipples. In an unheated area, if the temperature were to drop below freezing, water remaining in the system could damage it. This head has a chemical pellet fusible element that melts and allows the water to flow (photo 10).

Pendant. This sprinkler head hangs from under the piping. In some cases, it’s placed on a long “drop” and pokes through a dropped ceiling. The oblong device is a lead link holding the two levers together under tension. It’s designed to melt at a given temperature, releasing the arms and allowing water to flow (photo 11).

Sidewall. These were designed primarily for retrofitting hotels and motels. A pipe is placed along the upper corner of the corridor and a sprinkler head is inserted into each room and into the corridor itself. It operates like other standard sprinklers and will have a link, a glass bulb, or a chemical pellet (photo 12).

Early suppression fast response (ESFR). The insurance industry designed this head for high-piled storage warehouses (e.g., big-box stores and other places with high racks of combustible storage). Because of the large water demand, you need larger pipes than usual and, in most cases, a fire pump. If ever you’ve noticed sprinklers inside the racks in your favorite home supply store, they can be eliminated if an ESFR system in installed at the ceiling. It puts out lots of water really fast. Compare the difference in size between an ESFR and a standard head (photo 13). The “fast response” comes from a pencil-thin glass bulb that will burst a lot more quickly than a standard-size sprinkler bulb (photo 14).

High-pressure water mist sprinkler head. Developed by and for the cruise ship industry, these sprinkler heads can provide extinguishment into a compartment without necessarily flooding it. The water is discharged as a high mist fog and cools the atmosphere and the burning materials. Other applications include computer rooms instead of gas systems using halon and laboratory fume hoods where the scientists do their experiments. The water output from these heads is negligible, and they are also the only heads that have a filter screen on the nipple where it connects to the piping to eliminate any pipe scale, sludge, or other foreign matter that would be detrimental to the operation of this type of head. Note the quartzite bulb for activation (photo 15).

Tactical Tips

1. Always send personnel with a radio to the riser room on arrival to check the status of the sprinkler system.
2. Place a dry line from the first-due engine to the FDC, and prepare to augment pressure in the system. Know the local pressure demands for the systems in your district; also know that the rule of thumb for FDCs for sprinklers is 150 psi.
3. Shut sprinkler control valves only on the express order of the incident commander (IC). Let the system do what it was designed for, which is to confine, contain, and possibly extinguish the fire. ESFRs are designed to extinguish. Sprinklers will buy you some time to set up and get going.
4. Carry sprinkler head clamps to help minimize water damage. Sometimes two wood chocks work, but they would have to be cut to the right size.
5. Be ready to deploy salvage tarps for water traveling down to the floors below.
6. It’s extremely difficult and dangerous to fight a fire when sprinklers are operating. It is recommended that you don’t. The water from the heads is pushing the heat and steam down on top of you, and visibility is worse than usual. Coordinate your actions. Vent, shut the valve (by the IC’s order), and move in with a line as simultaneously as you can.
7. For stubborn deep-seated Class A or Class B fires, consider pumping finished foam solution into the FDC. Also consider pumping foam solution into FDCs feeding standpipe systems so you can have a foam handline if you need one on the upper floors of a building. We tried this in industry, and it worked! (“New Uses for Foam in Industry,” Fire Engineering, November 2001, http://bit.ly/1zHnRoQ). Standard sprinkler heads, although not necessarily listed for “foam service,” will effectively discharge foam.
8. Depending on your department’s policies, you may be expected to restore the system before you leave. There should be six spare heads and a wrench at the riser for this purpose. It is ultimately the owner’s responsibility to ensure that the system gets restored in a timely manner. Codes will not allow some occupancies to be occupied unless the sprinklers are in service (e.g., child care center), so immediate restoration of the system may be warranted vs. a “vacate” order.
9. If the swivels on the FDC are frozen, won’t spin, and won’t allow you to hook up, pull three feet of the line between your knees, and lock it there. Backtwist the line about seven turns and then place it on the frozen swivel and let it thread itself. Try this during a drill. Different thread types will bring different numbers of backtwists.

Sprinkler Training Tips for the Company Officer

One of the many responsibilities of the company officer is to ensure the members of his crew are familiar with active and passive fire protection. This segment on sprinklers (active fire protection) is key to understanding the basics of water-based fire protection systems. Knowledge of these systems lends itself to safe and efficient operations. Try these training tips to get your crew familiar with sprinklers:

1. Review the basic wet and dry systems as outlined. Explain the importance of knowing these systems and how they will help you fight the fire more effectively and how they assist with firefighter safety.
2. Review the tactical tips as outlined.
3. After review, go to the field and find these systems.
4. At a building in your response district, have the building engineer or other responsible party walk you through the systems.
5. Go to another building and have the members identify the components on the systems there. They need to know and understand the basics so when you send them to the “main control valve,” they’ll know what you mean.
6. Take advantage of your fire prevention bureau, fire marshal’s office, or fire academy. They have expertise in this area. Drop your pride, and improve your safety and fireground efficiency.
7. When you think your members know the basics, do it one more time. Just like standard tactics, knowledge of these systems needs to be second nature.
8. Make this part of your regular training, and take the time to examine these systems. Do it on or after runs or during downtime. If you’re driving by a building and you spot a water motor gong, an FDC, or a fire pump manifold, stop and take a look.

Ron Kanterman is the chief of the Wilton (CT) Fire Department and a 40-year fire service veteran with experience in municipal and industrial fire protection, volunteer and career services, emergency management, and emergency response. He has a bachelor’s degree in fire administration and master degrees in fire protection management and in environmental sciences. Kanterman is a contributing author to Fire Engineering, FireEngineering.com, Fire Engineering’s Handbook for Firefighter I and II, and the new edition of The Fire Chief’s Handbook. He co-hosts an FE Blog Talk Radio show “The Back Step Boys” and lectures around the country on various fire service topics. He is an adjunct professor of fire science and emergency management at the University of New Haven in Connecticut. Kanterman is also an advocate for the National Fallen Firefighters Foundation and its programs and is the chief of operations for the annual National Memorial Weekend.

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