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					Essentials of Fire Fighting,
         5th Edition

 Chapter 12 — Water Supply
        Firefighter I
Chapter 12 Lesson Goal

• After completing this lesson, the
 student shall be able to make hydrant
 connections and draft from a static
 water source according to the authority
 having jurisdiction (AHJ).




                  Firefighter I
                     12–1
Specific Objectives

 1. Describe dry-barrel and wet-barrel
    hydrants.
 2. Discuss fire hydrant marking and
    location.
 3. Summarize potential problems to look
    for when inspecting fire hydrants.

                                    (Continued)


                Firefighter I
                   12–2
Specific Objectives

 4. Explain the process of fire hydrant
    testing.
 5. Discuss alternative water supplies.
 6. Discuss rural water supply operations.
 7. Operate a hydrant. (Skill Sheet 12-I-
    1)
                                      (Continued)


                 Firefighter I
                    12–3
Specific Objectives

 8. Make soft-sleeve and hard-suction
    hydrant connections. (Skill Sheet 12-
    I-2)
 9. Connect and place a hard-suction
    hose for drafting from a static water
    source. (Skill Sheet 12-I-3)
10. Deploy a portable water tank. (Skill
    Sheet 12-I-4)
                 Firefighter I
                    12–4
Hydrants

• Usually made of cast iron with bronze
  working parts
• Must be opened and closed slowly to
  prevent damage




                 Firefighter I
                    12–5
Dry-Barrel Hydrants

• Installed in areas where
  prolonged periods of
  subfreezing weather are
  common
• Have main valve located
  below frost line that
  prevents water from
  entering hydrant barrel        (Continued)


                 Firefighter I
                    12–6
Dry-Barrel Hydrants

• Operation
• Must be completely open or closed to
  prevent leaking
• When shutting down, verify that water
  left in hydrant barrel is draining out


                                     (Continued)


                 Firefighter I
                    12–7
Dry-Barrel Hydrants

• In some areas, hydrants must be
  pumped out after each use to prevent
  water contamination
• If water is bubbling out of ground,
  broken component in barrel is allowing
  water to get past drain opening



                 Firefighter I
                    12–8
Wet-Barrel Hydrants

• Installed in warmer
  climates where prolonged
  periods of subfreezing
  weather uncommon
• Horizontal compression-
  type valve at each outlet
• Always filled with water

                 Firefighter I
                    12–9
Fire Hydrant Marking

• Rate of flow from individual hydrants
  varies for several reasons
• NFPA® has developed system of
  marking hydrants
• Local color-coding may differ from
  NFPA®


                 Firefighter I
                    12–10
Fire Hydrant Locations

• Decisions usually made by water
  department personnel based on
  recommendations from fire department
• Should not be spaced more than 300
  feet (100 m) apart in high-value districts


                                       (Continued)


                  Firefighter I
                     12–11
Fire Hydrant Locations

• Locate hydrant at every other
  intersection
• Intermediate hydrants may be required
  where distances between intersections
  exceed 350 to 400 feet (105 to 120 m)
• Other factors affect location/spacing


                 Firefighter I
                    12–12
Hydrant Testing and Inspections

• Responsibility of fire department
  personnel
• Firefighters should look for wide array
  of items




                  Firefighter I
                     12–13
Fire Hydrant Testing Process

• Many departments no longer responsible
  for testing
• Most basic test normally conducted is
  flow test




                 Firefighter I
                    12–14
Flow Test Steps

•   Select hydrant
•   Remove all outlet caps
•   Inspect outlet threads
•   Lubricate all outlet threads
•   Replace all caps except one 2½-inch (65
    mm) cap
                                      (Continued)


                   Firefighter I
                      12–15
Flow Test Steps

• Connect cap-type pressure gauge to
  outlet on second hydrant nearby
• Turn second hydrant on, record static
  pressure
• Turn test hydrant on fully, allow water
  to flow briefly

                                       (Continued)


                 Firefighter I
                    12–16
Flow Test Steps

• Use pitot tube, gauge to measure flow
  rate
• Record pitot gauge reading
• Take/record residual pressure reading
  from gauge connected to second
  hydrant before shutting test hydrant off

                                      (Continued)


                 Firefighter I
                    12–17
Flow Test Steps

• Turn off second hydrant, remove
    gauge, replace cap
•   Turn off test hydrant
•   Test for vacuum created by operating
    drain valve (dry barrel)
•   Replace cap on outlet
•   Repeat procedure with each hydrant

                   Firefighter I
                      12–18
Alternative Water Supply
Sources

•   Lakes
•   Ponds
•   Rivers
•   Ocean
•   Swimming pools
•   Farm stock tanks
•   Underground cisterns
                  Firefighter I
                     12–19
Drafting From Alternative Water
Supplies

• Process of drawing water from static
  source to pumper
• Can use almost any static source of
  water if sufficient in quantity, not
  contaminated
• Depth of water from which to draft


                 Firefighter I
                    12–20
Dry Hydrants

• Installed at static water sources to
  increase water supply available
• Usually constructed of steel or PVC pipe
  with strainers at water source, steamer
  ports to connect to pumper
• Designed to supply at least 1,000 gpm
  (4 000 L/min)
                                         (Continued)


                  Firefighter I
                     12–21
Water Shuttles

• Involve hauling water from supply
  source to portable tanks from which
  water may be drawn to fight fire
• Recommended for distances greater
  than ½ mile (0.8 km) or greater than
  the fire department’s capability of laying
  supply hoselines
                                       (Continued)


                  Firefighter I
                     12–22
Water Shuttles

• Critical elements
  – Fast-fill, fast-dump capabilities
  – Water supply officers at fill/dump sites
  – Traffic control
  – Hydrant operations
  – Hookups
  – Tank venting


                    Firefighter I
                       12–23
Water Shuttles

• Key components
• Dump site
• Portable tanks




                               (Continued)


               Firefighter I
                  12–24
Water Shuttles

• Ways in which water tenders unload
  – Gravity dumping
  – Jet dumps that increase flow rate
  – Apparatus-mounted pumps
  – Combination of these methods


                                        (Continued)


                   Firefighter I
                      12–25
Water Shuttles

• According to NFPA® 1901, water
 tenders on level ground should be
 capable of dumping/filling at rates of at
 least 1,000 gpm (4 000 L/min)



                                      (Continued)


                 Firefighter I
                    12–26
Water Shuttles

• To fill water tenders quickly, use best
  fill site, large hoselines, multiple
  hoselines
• Multiple portable pumps may be
  necessary




                   Firefighter I
                      12–27
Relay Pumping

• Can be used in situations where water
  source is close enough to fire scene to
  render water shuttles unnecessary
• Factors to consider
  – Water supply must be capable of
    maintaining desired volume of water
  – Relay must be established quickly
                                          (Continued)


                  Firefighter I
                     12–28
Relay Pumping

• Determining number of pumpers
 needed and distance between them
  – Several factors to take into account
  – Apparatus with greatest pumping capacity
    should be at water source



                                        (Continued)


                  Firefighter I
                     12–29
Relay Pumping

• Determining number of pumpers
 needed and distance between them
  – Large-diameter hose or multiple hoselines
    increase distance, volume a relay can
    supply
  – Water supply officer should consider all
    factors and determine correct distance


                   Firefighter I
                      12–30
Summary

• Because water is still the primary fire
  extinguishing agent used by firefighters
  in North America, and because fires
  often occur considerable distances from
  major water sources, fire departments
  must develop ways to transport
  available water from its source to where
  it is needed.                        (Continued)


                   Firefighter I
                      12–31
Summary

• Firefighters must know what water
 supply systems have been developed
 and what their responsibilities are when
 these systems are used.




                Firefighter I
                   12–32
Review Questions

1. What is the difference between dry-
   barrel and wet-barrel hydrants?
2. How are fire hydrants marked?
3. What factors affect hydrant location
   and spacing?


                                     (Continued)


                Firefighter I
                   12–33
Review Questions

4. List alternative water supplies.
5. What are three key components of a
   water shuttle operation?




               Firefighter I
                  12–34

				
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