2 Special Considerations Wet Systems, most frequently used. Designed for areas that are not subject to freezing.Dry Systems, used in areas that are subject to freezing.Preaction Systems, used in areas were additional precaution is desired to assure there is no water damage.Deluge Systems, used in areas that are considered to be a high hazard.
3 Residential systems, these system normally utilize a quick response type sprinkler head that affords a higher level of life safety for occupants. It should be noted that the residential type systems normally protect the occupied or living areas only.
4 Operational Sequence Wet-Pipe Systems Heat from a fire causes the heat-actuating plug in the sprinkler to drop from the frame.Water contained in the piping immediately discharges from the open sprinkler.As water begins to flow through the system, the alarm check valve on the water supply riser opens and activates the water motor gong and /or electronic signaling equipment.
5 The alarm is transmitted to a supervising agency or fire department. If needed, the volume and pressure of water in the system is boosted via a fire department pumper through the fire department connection.
7 Operational Sequence Dry-Pipe Systems Heat from a fire causes the heat-actuating plug in the sprinkler to drop from the frame.Pressurized air contained in the piping begins to flow through the open sprinkler.After a slight drop in air pressure, the quickopening device (if present) activates to accelerate the removal of air from the piping.
8 Once the air pressure is reduced sufficiently, the dry-pipe valve trips open. The interior clapper is held in the open position by a latch.Water enters the intermediate chamber of the dry-pipe valve. This automatically forces the automatic drip valve closed and begins the flow of water through alarm-signaling equipment.Water flows through the entire piping system and is discharged through the open sprinkler.
10 Operational Sequence Deluge System A product-of-combustion (heat, smoke, or flame) detector senses the presence of a fire condition ORAn individual working in the area discovers a fire in progress.The fire detection system sends a signal to the deluge valve, causing the valve to open. ORThe individual who discovers the fire manually trips the deluge valve.
11 As water enters the deluge valve and the piping, water flow indicator alarms are transmitted to signaling stations, and the water motor gong (if present) is activated.Water flow through all open sprinklers simultaneously.
18 Operational Sequence Preaction Systems A product -of-combustion (heat, smoke, or flame) detector senses the presence of a fire condition.The fire detection system sends a signal to the preaction valve, causing the valve to open.Sensors in the piping system detect the flow of water into the system and trigger the water flow fire alarm.When the level of heat at a sprinkler reaches the appropriate temperature, the sprinkler fuses and water flows through the open orifice.
19 Standpipe and Sprinkler Systems S.O.P. 30.5 Standpipe SystemsFor fire ground operations, the second arriving engine company will supply the standpipe system with 150 psi. + elevation loss per floor + friction loss.Elevation Loss = 5 psi. per floor or .5 psi. per footSprinkler SystemsNothing Showing:Alarm bell not ringing - water not flowing.The second arriving engine company will lay out hose and prepare to supply the system. The sprinkler system will not be charged unless ordered.The first arriving officer should give a situation report as soon as possible so as to assist in developing a plan of attack.Smoke of fire showing:Alarm bell ringing - water flowing.The first arriving engine company will supply the system with 150 psi. pump pressure.The first arriving officer at the scene of buildings equipped with standpipe and/or sprinkler systems may alter the standard operating procedure if necessary. However, the dispatcher will be informed immediately of the procedure change and ordered to replay this information to the second and third arriving companies so they can adjust their plans according.
20 It should be noted that a majority of all the standpipe systems in Chesapeake will be a combination sprinkler and standpipe system. In the event that you are supplying a standpipe system that is not part of the sprinkler system, the following is to be considered to determine pump pressure:Friction loss of hose from pumper to FDCFriction loss of hose on fire floorNozzle pressureElevationFriction loss in standpipe (25 psi)
21 Fire Department Connections (FDC) may be attached through walls or they may be a free standing type. Fire Department Connections may be designed to supply sprinkler systems or standpipe systems separately.The majority of all F.D.C.’s in Chesapeake are combination type connections which will supply both the sprinkler and standpipe system (when present).
26 Attached to the fire pump, you will see a regulating device Attached to the fire pump, you will see a regulating device. The purpose of this valve is to not allow the fire pump to drop the city’s pressure below a specified pressure (pre-set at factory for 20psi). This valve will automatically gate back the discharge of the fire pump to maintain the minimum specified city pressure. It may become necessary to supply the F.D.C. when residual pressures drop below 20 psi. and/or request the Water department to boost city pressure.
28 The following slide is affectionately know as a rose bud The following slide is affectionately know as a rose bud. In reality, it is a test header for the fire pump. A simple rule of thumb to remember is that each 2.5” discharge is equal to 250gpm.
30 Some wet sprinkler systems may have a small area of sprinkler heads that are on the out side of a building that may be subject to freezing. It is in these areas that a antifreeze loop is added to the existing wet system.
32 Hose stations through warehouses are normally 1” to 1. 5” pipe with 1 Hose stations through warehouses are normally 1” to 1.5” pipe with 1.5” valves. They are not normally used for major fire fighting but for moping up.
34 Standpipe connections may be located in stairwells at Hotels, High Rises, multi story schools, Hospitals, and other multi story facilities.Standpipe connections for shopping malls will normally be located at the entrances to the mall exit corridors. You will also find the standpipe connections at the mall entrances to the anchor stores.Standpipe connections may also be located at high hazard areas for example, grain elevators.
36 Standpipe Operations Accurately I.D. the fire floor. Establish control of the lobby.Evaluate conditions on the fire floor.Provide for the life safety of persons in immediate danger.Ensure an adequate water supply.Provide an initial attack on the fire.Check for fire extension and occupants on floors above the fire.
37 Note:Firefighters should connect their hose to the standpipe on the floor below the fire and advance the hose up to the fire floor.Excess hose can be laid up the stairway past the fire floor. This will make it feed easier onto the fire floor as it is pulled.Use SCBA’s. It would be good practice to carry a CO meter with crews that are in the stairwells or other floors that do not appear to be affected by visible smoke (lobby, staging, search, etc.).
38 High Rise / Mall Packs Hose, 150 feet. Valve wheel . Nozzle. Pipe wrench.Gated wye, 2.5 x 1.5 x 1.5 inch.Forcible entry tools.Spanner wrench.Rope hose tool.
39 Alternative Methods to Supply a Sprinkler and/or Standpipe System Use double 2.5 inch female on private yard hydrants that are part of the suppression system. You will need to use a city hydrant for your supply. ( Note: There should be a back flow prevention device which will protect the city’s water supply.)Use double 2.5 inch female on interior standpipe connection.Connect lines to aerial device and use as a standpipe.Use double male on FDC when the female swivel does not work.