DRIVER/ OPERATOR PUMPER
QUESTIONS AND ANSWERS
(GRADED A+)
Water - ANSWER-- most commonly used extinguishing agent
- noncombustible
- absorbs large amounts of heat
Waters Boiling Point - ANSWER-212° F
Waters freezing point - ANSWER-32°F
Waters Expansion Rate - ANSWER-1,700 to 1 at 500° F
Law of Specific Heat - ANSWER-Measures the ability of any substance to absorb
heat
Measured in BTUs (British Thermal Units)
1 BTU = the amount of heat required to raise 1lb of water 1°F
Law of Latent Heat of Vaporization - ANSWER-The amount of heat needed to turn a
liquid into a vapor
1 BTU to raise 1lb of water 1 degree up to 212° F
Adjustable Fog Nozzle - ANSWER-Straight Stream
Narrow Fog
Wide Fog
All 3 discharge at a rate of 100 gpm
The wider the pattern, the shorter the time span to fill a room with steam.
Advantages of Water - ANSWER-1. Can absorb large amounts of heat
2. As surface area increases, heat absorption increases
3. Water is plentiful in most areas
4. Steam occupies 1,700 times its original volume as water
Bottom - ANSWER-The pressure at the bottom is independent of the shape of the
liquid container above it
Equal - ANSWER-The pressure transmitted to a confirmed amount of water is
transmitted equally in all directions
Depth - ANSWER-The pressure of water in an open container is proportional to its
depth
,Perpendicular - ANSWER-The pressure on an amount of water is perpendicular to
any surface it acts on
All - ANSWER-At any point in the water in a container, pressure is equal in ALL
directions - including upwards
Density - ANSWER-The pressure of a liquid in an open container is proportional to
the density of the liquid
Disadvantages of Water - ANSWER-1. High surface tension limits its penetration into
dense materials
2. Incompatible with or reactive to certain fuels and combustible materials
3. Ice makes roofs and ladders slippery and can make equipment malfunction
4. Conducts electricity and makes work with energized electrical equipment
dangerous
Water Pressure - ANSWER-The force of water per unit area
PSI - ANSWER-pounds per square inch
The elevation of water defines psi
Column of water = 1 in x 1 in x 12 in = 0.434 psi
Height determines psi
6 Characteristics of Water - ANSWER-BED PAD
Bottom
Equal
Depth
Perpendicular
All
Density
Density = the materials weight compared to that of an equal quantity of water
6 Types of Pressure - ANSWER-1. Atmospheric
2. Head
3. Static
4. Flow
5. Residual
6. Normal operating
Atmospheric Pressure - ANSWER-The pressure the atmosphere experts on earth
Sea level = 14.7 psi
, Pounds Per Square Inch Gauge - ANSWER-PSIG
Shows with atmospheric pressure included in the reading
Pounds Per Square Inch Absolute - ANSWER-PSIA
The atmospheric pressure is included, so 14.7 should be subtracted from the overall
reading to obtain the true pressure
Head Pressure - ANSWER-Based on the force created by the height of a water
supply above the discharge point
To calculate = divide the head height by 2.3
Static Pressure - ANSWER-available pressure at a discharge point without water
flowing
Residual Pressure - ANSWER-water pressure in a distribution system that is still
available when a hydrant is flowing
Flow Pressure - ANSWER-the forward velocity of water at the discharge point
Measured in a pitot tube and gauge
If diameter of the discharge point is known, the gpm can be calculated
Normal Operating Pressure - ANSWER-water pressure in a distribution system
during regular consumption without any hydrants flowing
Friction Loss - ANSWER-The pressure lost that occurs between the pump and the
nozzle due to hose length and diameter
Reasons for Friction Loss - ANSWER-1. Control Valves
2. Hose and Coupling
3. Bends
4. Kinks
5. Adapters
6. Nozzle
7. In Line Gauge
Control Valves - ANSWER-Water molecules run against the inside surface of the
valves
Hose and Coupling - ANSWER-The smoother the hose lining the less the loss
Water molecules run against couplings
Bend - ANSWER-Water flow is forced to change direction
Kink - ANSWER-Sharp bends that restrict the flow of water
QUESTIONS AND ANSWERS
(GRADED A+)
Water - ANSWER-- most commonly used extinguishing agent
- noncombustible
- absorbs large amounts of heat
Waters Boiling Point - ANSWER-212° F
Waters freezing point - ANSWER-32°F
Waters Expansion Rate - ANSWER-1,700 to 1 at 500° F
Law of Specific Heat - ANSWER-Measures the ability of any substance to absorb
heat
Measured in BTUs (British Thermal Units)
1 BTU = the amount of heat required to raise 1lb of water 1°F
Law of Latent Heat of Vaporization - ANSWER-The amount of heat needed to turn a
liquid into a vapor
1 BTU to raise 1lb of water 1 degree up to 212° F
Adjustable Fog Nozzle - ANSWER-Straight Stream
Narrow Fog
Wide Fog
All 3 discharge at a rate of 100 gpm
The wider the pattern, the shorter the time span to fill a room with steam.
Advantages of Water - ANSWER-1. Can absorb large amounts of heat
2. As surface area increases, heat absorption increases
3. Water is plentiful in most areas
4. Steam occupies 1,700 times its original volume as water
Bottom - ANSWER-The pressure at the bottom is independent of the shape of the
liquid container above it
Equal - ANSWER-The pressure transmitted to a confirmed amount of water is
transmitted equally in all directions
Depth - ANSWER-The pressure of water in an open container is proportional to its
depth
,Perpendicular - ANSWER-The pressure on an amount of water is perpendicular to
any surface it acts on
All - ANSWER-At any point in the water in a container, pressure is equal in ALL
directions - including upwards
Density - ANSWER-The pressure of a liquid in an open container is proportional to
the density of the liquid
Disadvantages of Water - ANSWER-1. High surface tension limits its penetration into
dense materials
2. Incompatible with or reactive to certain fuels and combustible materials
3. Ice makes roofs and ladders slippery and can make equipment malfunction
4. Conducts electricity and makes work with energized electrical equipment
dangerous
Water Pressure - ANSWER-The force of water per unit area
PSI - ANSWER-pounds per square inch
The elevation of water defines psi
Column of water = 1 in x 1 in x 12 in = 0.434 psi
Height determines psi
6 Characteristics of Water - ANSWER-BED PAD
Bottom
Equal
Depth
Perpendicular
All
Density
Density = the materials weight compared to that of an equal quantity of water
6 Types of Pressure - ANSWER-1. Atmospheric
2. Head
3. Static
4. Flow
5. Residual
6. Normal operating
Atmospheric Pressure - ANSWER-The pressure the atmosphere experts on earth
Sea level = 14.7 psi
, Pounds Per Square Inch Gauge - ANSWER-PSIG
Shows with atmospheric pressure included in the reading
Pounds Per Square Inch Absolute - ANSWER-PSIA
The atmospheric pressure is included, so 14.7 should be subtracted from the overall
reading to obtain the true pressure
Head Pressure - ANSWER-Based on the force created by the height of a water
supply above the discharge point
To calculate = divide the head height by 2.3
Static Pressure - ANSWER-available pressure at a discharge point without water
flowing
Residual Pressure - ANSWER-water pressure in a distribution system that is still
available when a hydrant is flowing
Flow Pressure - ANSWER-the forward velocity of water at the discharge point
Measured in a pitot tube and gauge
If diameter of the discharge point is known, the gpm can be calculated
Normal Operating Pressure - ANSWER-water pressure in a distribution system
during regular consumption without any hydrants flowing
Friction Loss - ANSWER-The pressure lost that occurs between the pump and the
nozzle due to hose length and diameter
Reasons for Friction Loss - ANSWER-1. Control Valves
2. Hose and Coupling
3. Bends
4. Kinks
5. Adapters
6. Nozzle
7. In Line Gauge
Control Valves - ANSWER-Water molecules run against the inside surface of the
valves
Hose and Coupling - ANSWER-The smoother the hose lining the less the loss
Water molecules run against couplings
Bend - ANSWER-Water flow is forced to change direction
Kink - ANSWER-Sharp bends that restrict the flow of water
