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35 Cards in this Set
- Front
- Back
- 3rd side (hint)
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Advantages of Water
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-universal abundance
-ability to absorb heat -can be conveyed long distances -easily stored |
page 379
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List the three means of moving water:
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-Direct pumping system
-Gravity system -Combination system |
page 380
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Direct pumping system
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use one or more pumps that take water from the primary source and discharge it through filtration and treatment process where it is than pumped into the distribution system.
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page 380
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Gravity system
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the water is stored in an elevated storage tank above the distribution system.
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page 381
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When water flows through pipes,...
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its movement causes friction that results in a reduction of pressure.
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page 382
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dead-end hydrant
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a hydrant that only receives water from one direction.
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page 382
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circulating feed or a looped line
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a hydrant that receives water from two or more directions.
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page 382
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The water distribution grid systems consist of what?
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-Primary feeders
-Secondary feeders -Distributors |
page 382-383
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Primary feeders
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Large pipes (mains), with relatively widespread spacing, that convey large quantities of water to various points of the system for local distribution to the smaller mains.
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page 382
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Secondary feeders
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Network of intermediate-sized pipes that reinforce the grid within the various loops of the primary feeder system and aid the concentration of the required fire flow at any point.
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page 383
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Distributors
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Grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers.
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page 383
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Typical pipe size:
-Feeder -Secondary -Distributors |
-Feeder 16in
-Secondary 12 in -Distributors 8 in |
page 383
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Valves for water system are divided into...
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indicating and nonindicating.
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page 384
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indicating valves
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visually show whether the gate or valve is open, closed, or partially closed.
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page 384
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List the two types of indicating valves and briefly explain
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-PIV post indicating valve has a valve stem that operates with a handle and visually posts the words OPEN (white) or SHUT (red).
-OS&Y outside screw and yoke have a yoke on the outside with a threaded stem that controls the valve. If the stem is out the valve is open, if it is inside the valve is closed. |
page 384
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nonindicating valve
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are normally buried or installed in manholes but if properly buried/installed it can be control from aboveground through a valve box.
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page 384
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High friction loss could be caused by, what?
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Valves that are only partially open.
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page 385
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List the four types of pressure related to fire service:
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-Static pressure
-Normal operating pressure -Residual pressure -Flow pressure |
page 385
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Pressure (fire service)
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the velocity of water in a conduit (either pipe or hose) of a certain size measure in psi (pounds per square inch) or kPa (kilopascal).
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page 385
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static pressure
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Stored potential energy that is available to force water through pipe, fittings, fire hose and adapters. It is when water is not moving, this is why it is rarely found in a water supply system. In those cases it is defined as the normal pressure existing on a system before a flow hydrant is open.
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page 386
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Normal operating pressure
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The pressure found in a water distribution system during periods of normal consumption.
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page 386
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Residual pressure
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The part of the total available pressure that is not used to overcome friction or gravity while forcing water through pipe, fitting, fire hose, and adapters.
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page 386
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Flow pressure
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The forward velocity pressure at a discharge opening while water is flowing. This is the pressure we get when we test the hydrant with a pitot tube.
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page 386
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List and define the two types of fire hydrants
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Wet barrel and dry barrel
Wet barrel are used in areas where it doesn't freeze, have a valve at each outlet, and holds water to the valves near discharge as it is always filled. Dry barrel are used in areas where it freezes and the water is kept under a valve that is below the the freezing point. You operate that valve at the top of the hydrant and that releases the water into the hydrant. |
page 386 to 387
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NFPA Hydrant color code
Light blue |
Class AA 1,500 gpm or greater
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page 388
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NFPA Hydrant color code
Green |
Class A 1,000 to 1,499 gpm
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page 388
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NFPA Hydrant color code
Orange |
Class B 500 to 999 gpm
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page 388
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NFPA Hydrant color code
Red |
Class C Less than 500 gpm
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page 388
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In general, fire hydrants should not be spaced more than ________ apart in high-valve districts.
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In general, fire hydrants should not be spaced more than 300 FEET apart in high-valve districts.
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page 388
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Pitot tube measures
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the flow pressure coming from the hydrant.
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page 389
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drafting
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The process of raising water from a static source to supply a pumper.
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page 390
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When drafting from a natural source what must all suction lines have?
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A strainer so it doesn't get clogged or put in rocks, trash, etc. into the pumper or hose.
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page 390
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Water shuttle
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The hauling of water from a supply source to portable tanks from which water may be drawn to fight a fire. Recommend for distances greater than a half mile depending on department.
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page 391
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NFPA 1901 requires that apparatus on level ground be capable of dumping or filling at rates of at least...
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1,000 gpm
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page 392-393
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With relay pumping the apparatus at the water source should be the one with..
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the greatest pumping capacity.
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page 393
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