Transcript Pumping Apparatus Driver/Operator

Pumping Apparatus Driver/Operator
— Lesson 6
Pumping Apparatus Driver/Operator
Handbook, 2nd Edition
Chapter 6 — What Is Water and Where Does
It Come From?
Learning Objectives
1. Select facts about the characteristics of
water.
2. List the ways in which water has the ability
to extinguish fire.
3. Answer questions about specific heat.
4. Select facts about latent heat of
vaporization.
Pumping Apparatus Driver/Operator
(Continued)
6–1
Learning Objectives
5. Calculate latent heat of vaporization.
6. Answer questions about the surface area of
water.
7. Explain the ways in which water smothers
fire.
8. Select facts about specific gravity.
Pumping Apparatus Driver/Operator
(Continued)
6–2
Learning Objectives
9. List advantages of water as an extinguishing
agent.
10. List disadvantages of water as an
extinguishing agent.
11. Distinguish between pressure and force.
12. Explain how force is determined.
Pumping Apparatus Driver/Operator
(Continued)
6–3
Learning Objectives
13. State the principles of fluid pressure.
14. Match to their definitions terms associated
with pressure.
15. Explain how to measure atmospheric
pressure.
16. Calculate head pressure.
Pumping Apparatus Driver/Operator
(Continued)
6–4
Learning Objectives
17. List causes of friction loss in fire hose.
18. List causes of friction loss in piping systems.
19. List the principles of friction loss.
20. Answer questions about other factors
affecting friction loss.
Pumping Apparatus Driver/Operator
(Continued)
6–5
Learning Objectives
21. List ways to reduce friction loss.
22. Select facts about water hammer.
23. Name the four primary components of a
municipal water system.
24. Answer questions about the primary
components of a municipal water system.
(Continued)
Pumping Apparatus Driver/Operator
6–6
Learning Objectives
25. Select facts about water main valves.
26. Answer questions about water pipes.
27. Match to their definitions water system
consumption rates.
28. Select facts about private water supply
(Continued)
systems.
Pumping Apparatus Driver/Operator
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Learning Objectives
29. List the purposes of a private water supply
system.
30. List the advantages to have separate piping
arrangements in a private water supply
system.
Pumping Apparatus Driver/Operator
6–8
Characteristics of Water
• Water is a compound of hydrogen and oxygen
formed when two hydrogen atoms (H2)
combine with one oxygen atom (O).
• Between 32ºF and 212ºF (0ºC and 100ºC),
water exists in a liquid state.
(Continued)
Pumping Apparatus Driver/Operator
6–9
Characteristics of Water
• Below 32º F (0ºC) (the freezing point of
water), water converts to a solid state called
ice.
• Above 212ºF (100ºC) (the boiling point of
water), water converts into a gas called water
vapor or steam; it cannot be seen.
(Continued)
Pumping Apparatus Driver/Operator
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Characteristics of Water
(Continued)
Pumping Apparatus Driver/Operator
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Characteristics of Water
• Water is considered to be incompressible, and
its weight varies at different temperatures.
Note: Water is measured in pounds per cubic foot (kg/L)
(Continued)
Pumping Apparatus Driver/Operator
6–12
Characteristics of Water
• Water is heaviest close to its freezing point,
weighing approximately 62.4 lb/ft3 (1 kg/L)
• Water is lightest close to its boiling point,
weighing approximately 60 lb/ft3 (0.96 kg/L)
• For fire protection purposes, ordinary fresh
water is generally considered to weigh 62.5
lb/ft3 or 8.33 lb/gal (1 kg/L)
Pumping Apparatus Driver/Operator
6–13
Ways in Which
Water Extinguishes Fire
• Cooling
– By absorbing heat from the fire
• Smothering
– Water can be used to smother fires in combustible
liquids whose specific gravity is higher than 1.
– Smothering also occurs to some extent when
water converts to steam in a confined space.
Pumping Apparatus Driver/Operator
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Specific Heat
• The heat-absorbing capacity of a substance
• Amounts of heat transfer are measured in
British thermal units (Btu) or joules (J)
– A Btu is the amount of heat required to raise the
temperature of 1 pound of water 1ºF.
– The joule has taken the place of the calorie
(1 calorie = 4.19 joules).
(Continued)
Pumping Apparatus Driver/Operator
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Specific Heat
• Is the ratio between the amount of heat
needed to raise the temperature of a specified
quantity of a material and the amount of heat
needed to raise the temperature of an
identical quantity of water by the same
number of degrees.
• Of different substances varies. Refer to Table
6.1 on p. 136 of the manual.
Pumping Apparatus Driver/Operator
6–16
Latent Heat of Vaporization
• Is the quantity of heat absorbed by a
substance when changing from liquid to vapor.
• The temperature at which a liquid absorbs
enough heat to change to vapor is known as
its boiling point. At sea level, water begins to
boil or vaporize at 212ºF (100ºC).
(Continued)
Pumping Apparatus Driver/Operator
6–17
Latent Heat of Vaporization
• Vaporization does not
completely occur the
instant water reaches the
boiling point.
• Each pound of water
requires approximately
970 Btu (1 023 kJ) of
additional heat to
convert completely to
steam.
Pumping Apparatus Driver/Operator
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(Continued)
Latent Heat of Vaporization
• The latent heat of vaporization is significant in
fire fighting because the temperature of the
water is not increased beyond 212ºF during
the absorption of the 970 Btu for every pound
of water.
Pumping Apparatus Driver/Operator
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Surface Area of Water
• The speed with which water absorbs heat
increases in proportion to the water surface
exposed to the heat.
(Continued)
Pumping Apparatus Driver/Operator
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Surface Area of Water
• Water expands when converted to steam. At
212ºF (100ºC), water expands approximately
1,700 times its original volume.
(Continued)
Pumping Apparatus Driver/Operator
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Surface Area of Water
• Steam expansion is rapid inside a burning building.
The use of a fog stream in a fire attack requires that
adequate ventilation be provided ahead of the
hoseline.
Pumping Apparatus Driver/Operator
6–22
Ways in Which
Water Smothers Fire
• By floating on liquids
– Water floats on liquids that are heavier than water.
– If the material is water soluble, the smothering action
is not likely to be effective.
• By forming an emulsion
– Water smothers fire by forming an emulsion over the
surface of certain combustible liquids.
(Continued)
Pumping Apparatus Driver/Operator
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Ways in Which
Water Smothers Fire
• By forming an emulsion
– When a spray of water agitates the surface, the
agitation causes the water to be suspended in
emulsion bubbles on the surface; the emulsion
bubbles smother the fire.
– Emulsion bubbles can only form when the
combustible liquid has sufficient viscosity – the
tendency of a liquid to possess internal resistance
to flow.
Pumping Apparatus Driver/Operator
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Specific Gravity
• The density of liquids in relation to water
• Water is given a value of 1. Liquids with a
specific gravity less than 1 are lighter than
water and float on water. Those with a specific
gravity greater than 1 are heavier than water
and sink to the bottom.
• Most flammable liquids have a specific gravity
of less than 1.
Pumping Apparatus Driver/Operator
6–25
Advantages of Water as
an Extinguishing Agent
• Water has a greater heat-absorbing capacity
than other common extinguishing agents.
• A relatively large amount of heat is required to
change water to steam. This means that more
heat is absorbed from the fire.
(Continued)
Pumping Apparatus Driver/Operator
6–26
Advantages of Water as
an Extinguishing Agent
• The greater the surface area of water exposed,
the more rapidly heat is absorbed. The
exposed surface are of water can be expanded
by using fog streams or deflecting solid
streams off objects.
(Continued)
Pumping Apparatus Driver/Operator
6–27
Advantages of Water as
an Extinguishing Agent
• Water converted into steam occupies 1,700
times its original volume.
• Water is plentiful, relatively inexpensive, and
readily available in most jurisdictions.
Pumping Apparatus Driver/Operator
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Disadvantages of Water as
an Extinguishing Agent
• Water has a high surface tension and does not
readily soak into dense materials. However,
when wetting agents are mixed with water,
the water’s surface tension is reduced and its
penetrating ability is increased.
• Water may be reactive with certain fuels such
as combustible metals.
(Continued)
Pumping Apparatus Driver/Operator
6–29
Disadvantages of Water as
an Extinguishing Agent
• Water has low levels of opacity and
reflectivity that allow radiant heat to easily
pass through it.
• Water readily conducts electricity, which can
be hazardous to firefighters working around
(Continued)
energized electrical equipment.
Pumping Apparatus Driver/Operator
6–30
Disadvantages of Water as
an Extinguishing Agent
• Water freezes at 32ºF (0ºC), which is a
problem in jurisdictions that frequently
experience freezing conditions. Water freezing
poses a hazard to firefighters by coating
equipment, roofs, ladders, and other surfaces.
In addition, ice forming in and on equipment
may cause it to malfunction.
Pumping Apparatus Driver/Operator
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Pressure vs. Force
• Pressure
– Force per unit area
– May be expressed in pounds per square foot (psf),
pounds per square inch (psi), or kilopascals (kPa)
• Force
– A simple measure of weight
– Is usually expressed in pounds or kilograms
Pumping Apparatus Driver/Operator
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Determining Force
(Customary System)
• The weight of 1 cubic foot of water is
approximately 62.5 pounds.
• Because 1 square foot contains 144 square
inches, the weight of water in a 1-square-inch
column of water 1 foot high equals 62.5
pounds divided by 144 square inches
62.5 / 144 = 0.434 pounds
(Continued)
Pumping Apparatus Driver/Operator
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Determining Force
(Customary System)
(Continued)
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Determining Force
(Customary System)
• A 1-square-inch column of water 1 foot high
exerts a pressure at its base of 0.434 psi.
• The height required for a 1-square-inch
column of water to produce 1 psi at its base
equals 1 foot divided by 0.434 psi/ft.
• Therefore, 2.304 feet of water column exerts a
pressure of 1 psi at its base.
Pumping Apparatus Driver/Operator
6–35
Determining Force
(Metric System)
• A cube that is 0.1 m x 0.1 m x 0.1 m (a cubic
decimeter) holds 1 liter of water.
• The weight of 1 liter of water is 1 kilogram.
• The cube of water holds 1 000 liters of water
and weighs 1 000 kg.
(Continued)
Pumping Apparatus Driver/Operator
6–36
Determining Force
(Metric System)
• Because the cubic
meter of water is
comprised of 100
columns of water,
each 10 decimeters
tall, each column
exerts 10 kPa at its
base.
Pumping Apparatus Driver/Operator
6–37
Principles of Fluid Pressure
• First Principle — Fluid pressure is
perpendicular to any surface on which it
acts.
(Continued)
Pumping Apparatus Driver/Operator
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Principles of Fluid Pressure
• Second Principle — Fluid pressure at a
point in a fluid at rest is the same intensity
in all directions.
(Continued)
Pumping Apparatus Driver/Operator
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Principles of Fluid Pressure
• Third Principle —
Pressure applied to
a confined fluid
from without is
transmitted equally
in all directions.
(Continued)
Pumping Apparatus Driver/Operator
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Principles of Fluid Pressure
• Fourth Principle —
The pressure of a
liquid in an open
vessel is
proportional to its
depth.
(Continued)
Pumping Apparatus Driver/Operator
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Principles of Fluid Pressure
• Fifth Principle —
The pressure of a
liquid in an open
vessel is
proportional to the
density of the
liquid.
Pumping Apparatus Driver/Operator
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(Continued)
Principles of Fluid Pressure
• Sixth Principle — The pressure of a liquid
on the bottom of a vessel is independent
of the shape of the vessel.
Pumping Apparatus Driver/Operator
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Terms Associated with Pressure
• Atmospheric pressure — Pressure exerted by
the atmosphere at sea level (14.7 psi [101
kPa])
• psig — Pounds per square inch gauge; actual
atmospheric pressure = gauge reading
• psia — Pounds per square inch absolute; the
psi above a perfect vacuum, absolute zero(Continued)
Pumping Apparatus Driver/Operator
6–44
Terms Associated with Pressure
• Vacuum — Any pressure less than
atmospheric pressure
• Perfect vacuum — Absolute zero pressure
• Negative pressure — Gauge readings of less
than 0 psi or kPa
Note: The term negative pressure is technically a misnomer.
(Continued)
Pumping Apparatus Driver/Operator
6–45
Terms Associated with Pressure
• Head — The height of a water supply above
the discharge orifice
• Head pressure — The result of dividing the
number of feet that the water supply is above
the discharge orifice by 2.304
• Static pressure — Stored potential energy
available to force water through pipe, fittings,
(Continued)
fire hose, and adapters
Pumping Apparatus Driver/Operator
6–46
Terms Associated with Pressure
• Static — At rest or without motion
• Normal operating pressure — That pressure found in a
water distribution system during normal consumption
demands
• Residual pressure — That part of the total available
pressure not used to overcome friction loss or gravity
while forcing water through pipe, fittings, fire hose,
and adapters
(Continued)
Pumping Apparatus Driver/Operator
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Terms Associated with Pressure
• Residual — A remainder or that which is left
• Flow pressure (velocity pressure) — That
forward velocity pressure at a discharge
opening while water is flowing
• Elevation — The center line of the pump or
the bottom of a static water supply source
(Continued)
above or below ground level
Pumping Apparatus Driver/Operator
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Terms Associated with Pressure
• Altitude — The position of an object above or
below sea level
• Pressure loss — When a nozzle is above the
pump
• Pressure gain — When the nozzle is below the
pump
(Continued)
Pumping Apparatus Driver/Operator
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Terms Associated with Pressure
• Elevation pressure — Another term for both
pressure loss and pressure gain
• Friction loss — That part of the total pressure
lost while forcing water through pipe, fittings,
fire hose, and adapters
Pumping Apparatus Driver/Operator
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Measuring Atmospheric Pressure
• Compare the weight of the atmosphere with the weight
of a column of mercury.
Example: A pressure of 1 psi (6.9 kPa) makes the column of mercury
about 2.04 inches (52 mm) tall. At sea level, the column of mercury is
2.04 x 14.7, or 29.9 inches (759 mm) tall.
Pumping Apparatus Driver/Operator
6–51
Causes of Friction
Loss in Fire Hose
• Movement of water molecules against each
other
• Linings in fire hose
• Couplings
• Sharp bends
• Change in hose size or orifice by adapters
• Improper gasket size
Pumping Apparatus Driver/Operator
6–52
Causes of Friction
Loss in Piping System
• Movement of water molecules against each
other
• Inside surface of the piping
– The rougher the inner surface of the pipe, the
more friction loss
• Pipe fittings
• Bends
• Control valves
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Principles of Friction Loss
• First Principle — If all other conditions are
the same, friction loss varies directly with
the length of the hose or pipe.
(Continued)
Pumping Apparatus Driver/Operator
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Principles of Friction Loss
• Second Principle —
When hoses are the
same size, friction
loss varies
approximately with
the square of the
increase in the
velocity of the flow.
Pumping Apparatus Driver/Operator
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(Continued)
Principles of Friction Loss
• Third Principle — For the same discharge,
friction loss varies inversely as the fifth power
of the diameter of the hose
• Fourth Principle — For a given flow velocity,
friction loss is approximately the same,
regardless of the pressure on the water.
Pumping Apparatus Driver/Operator
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Other Factors
Affecting Friction Loss
• Water is practically incompressible. The same
volume of water supplied into a fire hose
under pressure at one end will be discharged
at the other end.
• Friction loss in a system increases as the
length of hose or piping increases.
• Flow pressure is greatest near the supply
source and lowest at the farthest point in(Continued)
the
system.
Pumping Apparatus Driver/Operator
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Other Factors
Affecting Friction Loss
• When the valve on the nozzle end of a hose is
opened, water flows moderately at a low
pressure. If the opening is made directly at the
hydrant, the flow will be much greater at a
higher pressure.
• Decreasing the amount of water flowing
through a hose reduces the speed of the
water in the hose; less friction loss occurs.
(Continued)
Pumping Apparatus Driver/Operator
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Other Factors
Affecting Friction Loss
• If velocity is increased beyond practical limits,
the friction becomes so great that resistance
agitates the entire stream, creating critical
velocity. Beyond this point, it becomes
necessary to parallel or siamese hoselines to
increase the flow and reduce friction.
Pumping Apparatus Driver/Operator
6–59
Ways to Reduce Friction Loss
• Minimize sharp bends or kinks in the hose by
using proper hose handling techniques.
• Reduce the length of the hose or increase its
diameter.
Pumping Apparatus Driver/Operator
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Water Hammer
• Suddenly stopping water moving through a
hose or pipe results in an energy surge being
transmitted in the opposite direction, often at
many times the original pressure. This surge is
referred to as water hammer.
• Water hammer can damage the pump,
appliances, hose, or the municipal water
system itself.
(Continued)
Pumping Apparatus Driver/Operator
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Water Hammer
(Continued)
Pumping Apparatus Driver/Operator
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Water Hammer
• Always open and close nozzle controls,
hydrants, valves, and hose clamps slowly to
prevent water hammer.
• Apparatus inlets and remote outlets should be
equipped with pressure relief devices to
prevent damage to equipment.
• High-volume systems should be protected
with dump valves.
Pumping Apparatus Driver/Operator
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Primary Components of
Municipal Water Systems
• Source of water supply
• Means of moving water
• Water processing or treatment facilities
• Water distribution system, including storage
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Source of Water Supply
• The primary water supply can be obtained
from either surface water or groundwater.
• Although most water systems are supplied
from only one source, there are instances
where both sources are used.
Pumping Apparatus Driver/Operator
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Means of Moving Water
• Direct pumping system
– Uses one or more pumps to take water from the
primary source and discharge it through the
filtration and treatment processes
– Includes a series of pumps that then forces the
water into the distribution system
(Continued)
Pumping Apparatus Driver/Operator
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Means of Moving Water
(Continued)
Pumping Apparatus Driver/Operator
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Means of Moving Water
• Gravity system
– Uses a primary water source located at a higher
elevation than the distribution system
– Works best when the primary water source is
located at least several hundred feet (meters)
higher than the highest point in the water
distribution system
(Continued)
Pumping Apparatus Driver/Operator
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Means of Moving Water
(Continued)
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Means of Moving Water
• Combination system
– Is a combination of a direct pumping system and a
gravity system
– Includes elevated storage tanks to supply the
gravity flow
(Continued)
Pumping Apparatus Driver/Operator
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Means of Moving Water
Pumping Apparatus Driver/Operator
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Water Processing or
Treatment Facilities
• The treatment of water for the water supply
system is a vital process.
• Water is treated to remove contaminants that
may be detrimental to the health of those
who use or drink it.
(Continued)
Pumping Apparatus Driver/Operator
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Water Processing or
Treatment Facilities
• The main concern regarding treatment
facilities is that a maintenance error, natural
disaster, loss of power supply, or fire could
disable the pumping station(s) or severely
hamper the purification process. Any of these
situations would drastically reduce the volume
and pressure of water available for fire
fighting operations.
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• The distribution system is the part that
receives the water from the pumping station
and delivers it throughout the area served.
• The ability of a water system to deliver an
adequate quantity of water relies upon the
carrying capacity of the system’s network of
pipes.
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• When water flows through pipes, its
movement causes friction that results in a
reduction of pressure. There is much less
pressure loss in a water distribution system
when fire hydrants are supplied from two or
more directions.
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• A fire hydrant that receives water from only
one direction is known as a dead-end
hydrant.
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• A fire hydrant that receives water from two
or more directions is called a circulating
feed or a looped line.
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• A distribution system that provides
circulating feed from several mains
constitutes a grid system, consisting of the
following components:
– Primary feeders
– Secondary feeders
– Distributors
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• Primary feeders — Large pipes with
widespread spacing that convey large
amounts of water to various points of the
system for local distribution to smaller mains
• Secondary feeders — Network of
intermediate-sized pipes that reinforce the
grid within the various loops of the primary
feeder system and aid the concentration of
(Continued)
the required fire flow
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• Distributors — Grid arrangement of smaller
mains serving individual fire hydrants and
blocks of consumers
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• To ensure sufficient water, two or more
primary feeders should run from the source of
supply to the high-risk and industrial districts
of the community by separate routes.
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• In residential areas, the recommended size for
fire hydrant supply mains is at least 6 inches
(150 mm) in diameter. These should be closely
gridded by 8-inch (200 mm) cross-connecting
mains at intervals of not more than 600 feet
(180 m)
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• In the business and industrial districts, the
minimum recommended size is an 8-inch (200
mm) main with cross-connecting mains every
600 feet (180 m)
(Continued)
Pumping Apparatus Driver/Operator
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Water Distribution System,
Including Storage
• Twelve-inch (300 mm) mains may be used on
principal streets and in long mains not crossconnected at frequent intervals.
• Water mains as large as 48 inches (1.2 m) may
be found in major cities.
Pumping Apparatus Driver/Operator
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Water Main Valves
• The function of a valve in a water distribution
system is to provide a means for controlling
the flow of water through the distribution
piping.
• Valves should be located at frequent intervals
so that only small districts are cut off if it is
necessary to stop the flow at specified points.
(Continued)
Pumping Apparatus Driver/Operator
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Water Main Valves
• Valves should be operated at least once a year to keep
them in good condition.
• One of the most important factors in a water supply
system is the water department’s ability to promptly
operate the valves during an emergency or breakdown
of equipment.
(Continued)
Pumping Apparatus Driver/Operator
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Water Main Valves
• Indicating valves
– Shows whether the gate or valve seat is open, closed,
or partially closed
– Are the most commonly used valves in private fire
protection systems
(Continued)
Pumping Apparatus Driver/Operator
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Water Main Valves
• Indicating valves
– Post indicator valve (PIV)
— A hollow metal post
attached to the valve
housing. The valve stem
inside has the words OPEN
and SHUT printed so that
the valve position is
shown.
Pumping Apparatus Driver/Operator
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(Continued)
Water Main Valves
• Indicating valves
– Outside screw and yoke
(OS&Y) — Has a yoke on
outside with threaded
stem that controls gate’s
opening or closing. The
threaded part of the stem
is out of the yoke when the
valve is open and inside
the yoke when the valve is
closed.
Pumping Apparatus Driver/Operator
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(Continued)
Water Main Valves
• Nonindicating valves
– Are buried or installed in manholes
– Are the most common types of valves used on
most public water distribution systems
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Water Main Valves
• Control valves
– Gate valves
– Butterfly valves
(Continued)
Pumping Apparatus Driver/Operator
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Water Main Valves
• If valves are installed according to established
standards, it normally will be necessary to
close off only one or perhaps two fire hydrants
from service while a single break is being
repaired. This cannot occur unless valves are
properly maintained and kept fully open.
(Continued)
Pumping Apparatus Driver/Operator
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Water Main Valves
• High friction loss is caused by valves that are
only partially open. A fire department will
experience difficulty in obtaining water in
areas where there are closed or partially
closed valves in the distribution system.
Pumping Apparatus Driver/Operator
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Water Pipes
• Water pipe that is used underground is
generally made of cast iron, ductile iron,
asbestos cement, plastic, or concrete.
• The internal surface of the pipe, regardless of
the material from which it is made, offers
resistance to water flow.
• Friction loss is increased by encrustation of
minerals on the interior surfaces of the pipe.
Pumping Apparatus Driver/Operator
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Water System Capacity
• Average daily consumption (ADC) — The
average of the total amount of water used in a
water distribution system over the period of
one year
• Maximum daily consumption (MDC) — The
maximum total amount of water that was
used during any 24-hour interval within a(Continued)
3-year period
Pumping Apparatus Driver/Operator
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Water System Capacity
• Peak hourly consumption (PHC) — The
maximum amount of water used in any
1-hour interval over the course of a day
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Private Water Supply Systems
• Private water supply systems are most
commonly found on large commercial,
industrial, or institutional properties.
• Private water supply systems may service one
large building or a series of buildings on the
complex.
(Continued)
Pumping Apparatus Driver/Operator
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Private Water Supply Systems
• Purposes
– To provide water strictly for fire protection purposes
– To provide water for sanitary and fire protection
purposes
– To provide for fire protection and manufacturing
processes
(Continued)
Pumping Apparatus Driver/Operator
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Private Water Supply Systems
• The design of private water supply systems is
typically similar to that of municipal systems.
• Most private water supply systems separate
piping for fire protection and domestic/
industrial services.
(Continued)
Pumping Apparatus Driver/Operator
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Private Water Supply Systems
• Advantages:
– The property owner has control over the water
supply source.
– Either of the systems are unaffected by service
interruptions to the other system.
Pumping Apparatus Driver/Operator
6–101
Summary
• All pumping apparatus driver/operators
should
– Understand the properties of water as a fire
extinguishing agent
– Know the factors that influence its delivery during
a pumping operation
– Be thoroughly familiar with the operation of the
apparatus to which they are assigned
(Continued)
Pumping Apparatus Driver/Operator
6–102
Summary
• Fire department personnel must also be
familiar with the design and reliability of both
public and private water supply systems in
their jurisdiction.
(Continued)
Pumping Apparatus Driver/Operator
6–103
Summary
• Large, well-maintained systems may provide a
reliable source of water for fire protection
purposes. Small capacity, poorly maintained,
or otherwise unreliable private water supply
systems should not be relied upon to provide
all the water necessary for adequate fire
fighting operations.
Pumping Apparatus Driver/Operator
6–104