12 - Water Supply Flashcards
Specific heat
The specific heat of any substance is the ratio between the amount of heat needed to raise the
temperature of a specified quantity of material and the amount of heat needed to raise the
temperature of an identical quantity of water by the same number of degrees. The specific heat of
water is 1:1.
Latent heat of vaporization
Latent heat of vaporization refers to the amount of heat absorbed by any substance when it is
converted from a liquid to a vapour.
Principle of friction loss
If all other conditions are the same, friction loss varies directly with the length of the hose or pipe
At what temperature will water be transformed from its liquid state to a solid state?
Temperature < than 0 Celsius
Water is transformed to a vapour at a ratio of ____________ to __________
1:1700
List the disadvantages of water when used as an extinguishing agent.
Water has high surface tension. High surface tension reduces the rate of heat
absorption.
Water reacts with certain materials.
Water has low opacity and low reflectivity therefore does not prevent the passage
of radiant heat well.
Water has low viscosity. This means it will not adhere well to vertical surfaces.
Water conducts electricity.
Steam from water can cause serious injuries.
How is the water distributed in the City of Edmonton?
Direct pumping into a grid system
Describe the difference between a dead end hydrant and circulating loop hydrant.
A dead end hydrant receives water from only one direction
An hydrant on a loop receives water from 2 direction
What is residual pressure in a water distribution system?
The pressure not needed to overcome friction or head pressure
Briefly describe the operation and uses of dry barrel hydrants.
A dry barrel hydrant is used in cold climates. The operating valve is at the base
of the barrel below the frost line. The barrel also has a drain valve system to
expel water when it is not in use. When the hydrant is in use the drain valve is
closed and when the hydrant is shut off the drain valve is open.
List sources of water:
Municipal water distribution system
Fire department vehicles with water storage tanks, portable tank
Wells, pools, cisterns
Rivers, lakes, ponds, Creeks
List alternate methods to supply water at a fire scene.
Drafting
Relay pumping
Water shuttle
Tankers
List the color of hydrant caps and their respective flow rate.
Black/Light Blue More than 5700L/Min
Green - 3800 - 5700 L/Min
Yellow Orange - 1900 - 3800 L/Min
Red - Less than 1900 L/Min
1900 Lpm each category
What do rings on the hydrant indicate?
Know colours and meanings
The service status of the hydrant
Green: under construction (do not use)
Blue: Hydrant in use (with permission)
Orange: Out-of-service (non-operational)
White: Fire dept. use only
List the three basic elements of a water shuttle
Fill site
Dump site
Shuttle
List the four types of hose damage.
Mechanical
Chemical
Thermal
Organic
44 mm Fog Nozzle: Flow, NP and FL per length
550 Lpm
500 Kpa
100 Kpa/length
65 mm Fog Nozzle: Flow, NP and FL per length
950 Lpm
500 Kpa
50 Kpa/length
Elevation pressure changes per floor
35 Kpa per floor
10 Kpa per metre
Big Gate position summary:
Sits behind captain
1: Safely Dismount with PPE and Radio
2: Remove hydrant gate from rear
3: Wrap hose
4: stand on hose and signal small gate when ready
5: when safe, remove steamer cap
6: inspect barrel
7: connect hydrant gate
8: radio or signal driver or sector officer water is ready
9:Open hydrant when ordered
10: Gather tools, remove kinks and report for reassignment
Small Gate position summary:
Sits behind operator
1: Safely dismount wearing PPE w radio
2: Open coffin doors
3: Grab hydrant kit
4: Place kit near hydrant
5: Help big gate w supply line and wait for ready signal
6: Return to position in truck and relay ready signal
7: At the scene: dismount and un couple supply line
8: attach to intake, use pony if necessary
9: communicate line is ready
10: report for reassignment
