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					                                                               Relay Pumping Operations




                             Relay
                            Pumping
                           Operations
                                       Instructors
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                                                                          INITIAL 12/99

                               FOR MORE INFORMATION CONTACT COURSE COORDINATOR AT

                                                            MISSISSIPPI FIRE ACADEMY
                                                                #1 FIRE ACADEMY USA
                                                                    JACKSON, MS 39208

NFPA 1001 - I&II FIREFIGHTER                                                      IG 1

                                CERTIFICATION DIVISION
                                 Mississippi Fire Academy
                                                                           Relay Pumping Operations




                                                                                      (601) 932-2444

Subject:        Relay Pumping Operations

Time:          45 minutes

Objectives:
3-2.2/6-2.2 Pump a supply line of 2 " or larger, given a relay pumping evolution, the length
and size of the line, desired flow and intake pressure, so that the proper pressure and flow are
provided to the next pumper in the relay.

               (a) Requisite Knowledge: Safe operation of the pump

               (b). Requisite Skills: The ability to position a fire department pumper to operate
               at a afire hydrant and at a static water source, power transfer from vehicle engine
               to pump, draft, operate pumper pressure control systems, operate the
               volume/pressure transfer valve(multistage pumps only), operate auxiliary
               cooling systems, make the transition between internal and external water
               sources.




NFPA 1001 - I&II FIREFIGHTER                                                                   IG 2

                                    CERTIFICATION DIVISION
                                     Mississippi Fire Academy
                                                             Relay Pumping Operations




                                          Outline

I. Relay Apparatus and Equipment

II. Relay Pumping operational Considerations

III. Types of Relay Pumping Operations
       A. Maximum Distance Relay Methods
       B. Constant Pressure

IV. General Guidelines for Relay Operations
      A. Putting the Relay into Operations
      B. Operating the Relay
      C. Shutting Down the Relay




NFPA 1001 - I&II FIREFIGHTER                                                    IG 3

                                 CERTIFICATION DIVISION
                                  Mississippi Fire Academy
                                                                       Relay Pumping Operations




                    Introduction
                    In some fire situations, the source of water may be a considerable distance
                    from the fire. When faced with this, pumping operations must relay the
                    water to the fire scene. Relay operations use the pumper at the water
                    source to pump water under pressure through hoselines to the next
                    pumper. Components of a relay operation, factors that influence the relay,
                    and various methods for establishing a relay operation will be discussed in
                    this chapter.

Slide 4      I. Relay Apparatus and Equipment
                    Various pieces of equipment are used. Standard fire apparatus are used for
                    pumping
                           A. Explanation of terms
                                  1. Source pumper- connected to the water source
                                  2. Relay pumper (in-line pumper)- connected within the
                                  relay and receives water
                                  3. Attack pumper- located at the fire and receives water
                                  4. Hose tenders
                                          a. May or may not have a pump
                                          b. Usually carry large amounts of hose (LDH),
                                          tools and appliances

Slide 5             B. Variety of appliances may be used
                                   1. Intake pressure relief valves- (2 types)
                                          a. Supplied by pump manufacturer
                                          b. Add-on device
                                   Both should be preset within 10 psi of static pressure or
                          above the discharge pressure of previous pumper
                                          c. Bleeder valves- allows air to e bled off

Slide 6      II. Relay Pumping Operational Considerations
                     Relay operations are based on:


NFPA 1001 - I&II FIREFIGHTER                                                               IG 4

                                CERTIFICATION DIVISION
                                 Mississippi Fire Academy
                                                                      Relay Pumping Operations



                                 Amount of water
                                 Distance from emergency scene to the water source

                           A. Amount of water
                                1. Relay may supply total water needed
                                2. Relay may supplement

                           B. Distance
                                  1. The longer the distance, the longer the hose lay
                                         a. More friction loss
                                         b. Size of hose affects flow
                                         c. Number of pumpers needed

                                  2. To increase amount of water
                                         a. Increase hose size or number of hoses


Slide 7      III. Types of Relay Pumping Operations
                    Two determining factors:

Slide 8             A. Maximum Distance Relay Method
                         Involves flowing a predetermined volume of water for the
                         maximum distance it can be pumped.

                                  1. Note Table 13.1 to determine number of pumpers
                                  needed.

Slide 9             B. Constant Pressure Relay Method
                          Used constant pressure by establishing maximum flow

                                 Speeds relay activation
                                 Requires no complicated calculations
                                 Radio traffic and confusion is reduced
                                 The attack operator governs with greater ease
                                 Operators only have to adjust to one constant pressure

Slide 10                          1. Forming the Constant Pressure Relay

NFPA 1001 - I&II FIREFIGHTER                                                               IG 5

                                CERTIFICATION DIVISION
                                 Mississippi Fire Academy
                                                                     Relay Pumping Operations



                                         a. Position the attack pumper
                                         b. Place largest pumper at the source
                                         c. Lay out hose
                                         d. Connect all hose to all pumpers in relay
                                         e. All D/O open discharges except source
                                         f. Source pumper develops 175 psi
Slide 11                                 g. D/O closes discharges slowly & throttle to 175
                                         psi
                                         h. Set relief valve or governor

                                 2. Keep pressure until
                                       a. Intake pressure drops below 20 psi
                                       b. Throttling does not increase rpm

                                 3. Constant pressure can be modified for:
                                       a. Pumper spacing
                                       b. Elevation differences
                                       c. Increases in needed flow
                                       d. LDH hose


Slide 12           IV. General Guidelines for Relay Operations

                          A. Putting the Relay into Operation
                                 1. Always begins with the source pumper- largest pumper
                                 2. When water is established, use a dump line until relay is
                          ready.
                                         a. When discharge begins, slowly close dump line
                                 and keep residual below 50 psi.
                                 3. In receiving water, relay pumpers should maintain 20-30
                                 psi residual.
                                         a. If residual is greater than 50 psi, open dump line
                                         b. As discharge increases, residual decreases

Slide 13                  B. Operating the Relay
                                1. Once in operation, set pressure control device
                                        a. Operate auxiliary cooler for extended operations


NFPA 1001 - I&II FIREFIGHTER                                                             IG 6

                               CERTIFICATION DIVISION
                                Mississippi Fire Academy
                                                           Relay Pumping Operations




                          C. Shutting Down the Relay




NFPA 1001 - I&II FIREFIGHTER                                                  IG 7

                               CERTIFICATION DIVISION
                                Mississippi Fire Academy

				
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