Chapter 12 Water Supply Flashcards
(106 cards)
Explain the characteristics of water
Water, a hydrogen and oxygen compound (H2O), exists in a liquid state between 0°C and 100°C, a solid state below 0°C, and converts to vapour or steam above 100°C. It is cheap, usually plentiful, and is the most common extinguishing agent. It works by cooling the fire to below the
temperature required to support combustion, by smothering the flames, and also by cooling items not involved below their ignition temperature
Describe the City water supply system
- Intakes located in the middle of the river at the E.L. Smith and Rossdale water treatment sites
- The water distribution system in Edmonton uses the ‘Direct Pumping’ method to move all their water
- There are over 59 pumps within the system
- Also use reservoirs for storage
800 million liters (176 million Imperial gallons) of water within the system - 50 million liters (11 million Imperial gallons) allocated for fire protection
- Water Main Valves within system allows for total control of water flow
- Zone Separation Valves may experience low pressures and volume at first, System sensors will automatically open check valves to stabilize to normal
- Water distribution system’s pipe sizes –
● >400mm Primary lines
● 300-400mm Feeders
● 200-300mm Distribution
● Can go up to 1500mm
What are the alternate water supply available to the fire service
- Rivers
- Ponds
- Pools Cisterns
- Portable tanks
Describe fire hydrant and its operation.
Fire Hydrants are the main water source for fighting fires. In this cold region the cities and municipalities use a dry barrel hydrant system. When installed, the valve that controls the water flow is located below the frost line to prevent freezing in the system. The hydrant is also equipped with a drain valve at the base to prevent any water from remaining in the barrel. When the hydrant is not in use the drain valves at the base of the hydrant are in the open position to provide drainage, and when the hydrant is in use or flowing the drain valve is closed.
What are the sizes and lengths of hoses used in the EFRS
25 mm –Booster reels (tankers/ATPs/Two Stage Pumps)
38 mm – Wildland (Seasonal)
44mm – Hi-Combat Attack hose
65mm – Hi-Combat Attack hose
125mm – Hi-Volume Hose – aka supply hose
150 mm Soft Suction
Found in 15m and 7.5m (PONY) lengths for the 125mm
What types of damage a hose may be subjected
Mechanical
Thermal
Organic
Chemical
What are the care, cleaning procedure of hose (5 points)
- Ensure that all the hose is cleaned using mild soap and water.
- Hang all wet hose in the drying tower with the exception of “combat hose” and the high volume hose
- Examining hose for damage/contamination, and reporting such conditions to the Station Officer
- Rolling all dried hose, and placing in the station racks.
- Hose should not hang in the drying tower for more than 48 hrs
What are the types and parts of hose couplings
The Higbee cut & Indicator
Threaded coupling
Storz Coupling
Describe the type of hose roll used by EFRS
Straight hose roll
Describe the type of hose load used by EFRS
- Flat load- The flat load is used for the 125 mm HI VOL supply line as well as the 65mm Attack hose - both on the rear bed and the transverse beds of the units equipped with 65 mm hose.
- Scorpion Hose Load- The Scorpion hose load is an effective way of packaging the 2 lengths of 44mm Attack hose in our jump-line compartment, allowing one firefighter to easily deploy the hose without issues.
What is the SPECIFIC HEAT of any substance
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.
What is Latent Heat 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.
(This is important because it is the reason behind water’s
cooling effect. When 3.785 L of water at 16°C is converted to steam, it will absorb more than
2508 kJ of heat.)
What are the 4 types of pressure within the water supply system
- Static Pressure – pressure of the water when it is not moving.
- Normal Operating Pressure - pressures within the water distribution system during normal consumption demands.
- Residual Pressure - total available pressure not used to overcome friction or gravity when water is flowing through the system.
- Flow Pressure - forward velocity pressure at any discharge opening.
What is water hammer
Water hammer is the term used to describe the destructive forces, evident in pounding noises and
vibrations, which develop in a piping system when a column of non-compressible liquid flowing
through a pipe line at a given pressure and velocity is stopped abruptly.
what is the difference in the pressure exerted by flowing water against a closed system versus the static pressure (during water hammer)
seven times or more than the static pressure. However, you can open and close a 44mm line as fast as you want and it will have little effect on the hose or couplings.
How do you prevent water hammer
Water hammer can be prevented by opening and closing valves and nozzles slowly.
Water hammer can occur in hydrants as well, open and close slowly and completely.
It is important to remember what about operating a fire hydrant
the hydrant must be either fully open or fully closed.
What direction do you need to turn the key to pen or close the hydrant
- Open hydrants by turning key in a counter-clockwise direction
- Close hydrants by turning key in a clockwise direction
Water flow capabilities of a hydrant is indicated by the color of the
dome and caps What are the colors and flows for each
● Blue / Black / Silver - Greater than 5700 LPM
● Green - 3800 – 5700 LPM
● Yellow Orange - 1900- 3800 LPM
● Red - Less than 1900 LPM
There are four different
colours of hydrant rings, each with its
respective meaning. What are they?
- Orange - Out of Service (non-operational)
- Blue - Hydrant in Use (with permission)
- White - Fire department Use Only
- Green - Under Construction (do not use – no water)
What are The three basic elements of a water shuttle operation
- Dump site – the attack apparatus at the fire scene, or a secondary pump that is relaying water to the attack pump, drafting from the portable tank or when a Rural Hitch is set up.
- Fill site – the fill apparatus at the water supply
- Shuttle – the mobile water apparatus that hauls the water from the fill site to the dump site.
What are the capacities of the tankers
– Smaller Smeal Tanker holds 4500L while the Smeal Supertanker carries 13,500L.
What is the On Board Water capacity of the EFRS units
Pumps → 1817 Litres (1890 Litres - New Two Stage Pumps)
Ladders → 1134 Litres
Tankers → 4500 Litres
Super Tankers → 13,500 Litres
New Super Tankers → 11, 376 Litres
ATP → 1442 Litres
Mule trailer → 250 Litres
There are four categories of hazards to fire hoses:
Mechanical
Thermal
Organic
Chemical.