Exam Questions Flashcards
Water services designed the grid system to supply water for commercial, residential and firefighting. What percentage is intended for commercial and residential combined?
20%
The maximum space between hydrants in a residential area is?
300 meters
The maximum space between hydrants in an industrial area is?
150 meters
To achieve the required flow, water services allows the us of how many hydrants?
3
How far away does the second hydrant need to be to have minimal impact on the initial water supply system
2 blocks
How often are hydrants updated on the MDT?
Quarterly
Friction loss is reduced by using?
Large diameter hose
What is the damaging force created by quickly stopping water that is flowing in a closed system known as?
Water hammer
If the nozzle is at a higher elevation than the pump, the static nozzle pressure will be _________ the pressure at the pump??
Lower than
Friction loss is caused by?
Kinks and bends
Couplings
Movement of water in the hose
the city of Calgary water system has how many pressure zones?
47
At sea level atmospheric pressure is equal to?
100kPa (14.7psi)
Under extreme circumstances the fire department can boost system pressure by pumping back into a hydrant? True or False
False
How much greater can the FL of an old hose be compared to that of a new hose?
As much as 50% greater
The transfer valve allows the two stage pump to run in which two positions?
Pressure and volume
City of Calgary hydrants are on what type of a system?
Grid system
What is a secondary feeder line?
A network of intermediate sized pipes that reinforce the grid within the various loops of the primary feeder system
What is a primary feeder line?
Large pipes, with relatively widespread spacing that carries large quantities of water to various points of the system for local distribution into smaller mains
What is a distributor line?
The grid arrangement of smaller mains serving individual fire hydrants and city block consumers
what is a dead end hydrant?
A hydrant that receives water flow from only one direction
How much water does a drop tank hold?
14,000 litres
How much does 1 cubic meter of water hold and weigh?
Holds 1000 Litres and weighs 1000kg
When pumping multiple lines of different pressures the PSG is set to which line?
The line with the highest pressure. All other lines are gated back
The overheat protection manager prevents the pump from overheating by?
Dumping water from the pump onto the ground
The gradually increasing size of the waterway ________ the velocity of the water thus enabling the pressure to ___________ proportionally
Decreases and build up
On a centrifugal pump water enters the impeller through the ?
Eye
At sea level the pump can theoretically lift water how high?
10m
What is the difference between vanes and valutes?
Vanes transmit motion to the water, volutes carry the water away from the impeller/pump
Most CFD apparatus have a water capacity of how many litres?
2500L
When bringing on a hydrant the operator should do what two things to compensate for potential spike?
Raise the pump discharge pressure and lower the hand line pressure
What is direct application when talking about foam application?
Generally limited to class A foam applications. As implied foam is applied directly to the burning material
What is the rain down method when talking about foam application?
Used when other methods of application are not feasible due to elevation or the nature of the fuel container. stream is directed above the container and foam is allowed to rain down onto the surface of the fuel
What is the bank down method when talking about foam application?
Used when a vertical surface is available near or within the area of the ignitable liquid. The foam stream is directed onto the vertical surface allowing the foam to run down and spread across the surface of the fuel
What is the roll on method when talking about foam application?
The foam is directed onto the ground near the pool or the spill. The foam rolls across the surface until the entire surface is covered and the fire is extinguished. This method is only used on open ground
What is a polar solvent?
Mixes readily with water. Ex. Acetone, isopropanol, methanol, alcohol
Polar solvents destroy regular foams
What is a hydro carbon?
Does not mix readily with water
Ex diesel, gasoline, oil
Dumping the tender by pumping it out through a hose is more efficient than using the dump valve? True or false
False
A dry hydrant for drafting is a hydrant that?
Is used for drafting from a static supply
The steps to start drafting (with the pump in gear) are?
Put the PSG in RPM mode at approximately 1100 RPM. Pull.push the primer until the pressure appears on the discharge, open a discharge
To increase shuttle efficiency FF should do what?
Maintain training on filling and dumping tenders
The priming pump is what kind of pump?
Positive displacement pump
When filling the booster tank be sure not to do what?
Cavitate the pump