Chapter # 12 Static Water Supply Sources Flashcards
The height of the fire pump above the surface of the water.
Lift
What is the height of possible lift affected by?
Atmospheric pressure and the amount of vacuum the primer can produce.
What height could a fir pump lift water at sea level in a theoretical scenario?
33.8’
The maximum height to which any amount of water may be raised through a hard intake hose to the pump.
Maximum lift
What is the maximum lift for most fire pumps, in most circumstances?
25’
What is the equation to determine the max lift that a pumper will accomplish?
L=1.13 Hg Multiply 1.13 by the inches of mercury reading on the intake gauge. This will give you the max possible lift in feet.
The height of a column of water may be lifted in sufficient quantity to provide a reliable fire flow.
Dependable lift
When taking in to consideration atmospheric pressure and friction loss, every fire pump in good repair should have a dependable lift of what?
14.7’
All fire pumps are rated when drafting from 10’ of lift with how much hard inake hose?
20’
What capacity if pump able to deliver when lifting 15’? How about 20’?
15' = 70% of rated capacity 20' = 60% of rated capacity
Takes into account all factors that contribute to the amount of work that the pump must do to provide a fire stream.
Net Pump Discharge Pressure
What is the equation for NPDP when drafting?
PDP + Intake pressure correction
Intake pressure correction equation.
Pressure correction = lift + total intake hose FL / 2.3
What are the two static water supply sources firefighters can draw from?
Natural and man made.
What two factors should be considered when determining a natural water drafting site?
Adequacy and Accessibilty
What is the equation for determining the adequacy of a small stream?
Q=AxVx7.5 Q= flow. A= sqauare feet (width x depth). V=Velocity in ft/min
What is the rule of thumb for evaluating a small pond or lake for adequacy?
Evey 1’ of depth for an area of 1 acre = 1,000 gpm for 5 hours.
Name some potential water source accessibility factors.
Can reach water with pumper. Wet or soft ground. Inadequate depth. Silt or debris. Freezing weather. Swift water.
What should be done when pumpers are can not reach the water supply source but it is the only source available?
Use portable pumps to pump water from the source to the pumper.
Name two common cause for ground thawing around a apparatus.
Apparatus exhaust heat. Warm water from the pump spilling onto the ground.
If a apparatus is in a effective position and drafting operations have started, then sinking start to occur, what should be done?
Remain there until the operation is complete.
What can be used to build a damn to increase the water depth to help drafting from a stream?
A ladder and salvage cover.
What can be placed in the water to provide a drafting spot when it freezes?
Barrels. plastic garbage cans. wooden plugs.
What tools may be used to cut a hole though ice to gain access for drafting?
Axe, chain saw, power auger.
List some common man made water supply sources.
Cisterns. Private water storage tanks. Ground reservoirs. Swimming pools. Agricultural irrigation systems.
Underground water storage receptacles that are usually found in areas that are not serviced by a hydrant system. Typically receive their water from wells or rainwater runoff.
Cisterns
What sizes do cisterns typically come in?
10,000 to 100,000 gallons.
What are two ways to access the cistern water?
Removable man hole cover or a dry hydrant.
Where are private water storage tanks commonly found?
Large residential, industrial, and agricultural properties.
Technically a elevated water tank is not a what?
Static water source.
Man made impoundments that have some characteristics of a pond or small lake. Most often found on commercial or industrial properties and at water treatment facilities. Contain many millions of gallons of water.
Ground reservoirs.
Do some communities require swimming pool owners to allow access to fire firefighters to draft from the swimming pool?
Yes
What is a unique problem with drafting from swimming pools.
They are often fenced in.
Most pools contain enough water to extinguish a fire where?
In a single family home.
What is the equation for capacity of a square/rectangular pool?
Capacity in gallons = L x W x D x 7.5
What is the equation for capacity of a circular pool?
Capacity in gallons = pie x r squared x D x 7.5
Pie = 3.14 r = radius or 1/2 diameter in feet.
How is irrigation water generally transported?
open canals or portable pipes (more common)
What may be needed to access water from a portable pipe agricultural water system?
Special adapters and tools.
