Download Fire Apparatus Driver/Operator - Pumper Module 4 and more Exams Advanced Education in PDF only on Docsity!
Fire Apparatus Driver/Operator - Pumper
Module 4
One gallon of water weighs? - correct answer 8.33 lbs Water freeze and boil temperatures? - correct answer Freezes: 32° F Boils: 212° F Water expansion ratio at 500° F. - correct answer 1,700 to 1 Law of Specific Heat - correct answer Ability of any substance to absorb heat. Water is the standard for measuring specific heat and is given a value of 1. Specific heat is measured in British Thermal Unites (BTUs). Latent Heat of Vaporization - correct answer The amount of heat needed to turn a liquid into a vapor. It takes one BTU to raise one pound of water 1°, up to 212° F. Once water reaches 212° F, each pound requires an additional 970 BTUs to convert it to steam. Knowledge Check 1
- Most extinguishing agents require less than one BTU to raise their temperature 1° F.
- This is the heat absorbing capacity of a substance.
- Water absorbs over 950 additional BTUs going from 212° F to steam.
- This is the amount of heat needed to turn a liquid into a vapor. - correct answer Law of specific Heat 1 & 2 Law of Latent Heat of Vaporization 3 & 4 Heat Absorption - correct answer Speed at which water absorbs heat depends upon the amount of water surface exposed to the heat. Example Fog nozzle flowing at 100 gpm for a room 96x50x10 will fill a room with steam using the different patterns. - correct answer Straight Stream: 9 Minutes Narrow Fog: 6 Minutes Wide Fog: 1.5 Minutes Advantages of water as an extinguishing agent - correct answer Can absorb large amount of heat before turning to steam As surface area increases, heat absorption speeds up Steam occupies 1,700 times its original volume as water Water is plentiful in most areas. Disadvantages of water as an extinguish agent - correct answer High surface tension limits its penetration into dense materials
E = Equal D = Depth P = Perpendicular A = All D = Density Characteristics of Water Pressure Definitions - correct answer Bottom = Pressure at the bottom of a container Equal = Pressure transmitted to a confined amount of water is transmitted equally in all directions. Depth = Pressure of water in an open container is proportional to its depth Perpendicular = Pressure on an amount of water is perpendicular to any surface it acts on All = At any point in the water in a container, pressure is equal in all directions, including upwards. Density = Pressure of a liquid in an open container is proportional to the density of the liquid. The density of a liquid refers to the material's weight compared to that of an equal quantity of water. Water is given the weight of "one"; other materials are either lighter (<1) or heavier than water (>1). Knowledge Check 3
You're presented with a column of water three feet by three feet, with a height of one foot. The water pressure of this column equals: - correct answer A. 0.145 psi B. 0.434 psi (Correct Answer) C. 0.868 psi D. 1.302 psi Knowledge Check 4 Identify Two characteristics of water pressure - correct answer A. The pressure on water is parallel to any surface it acts on. B. The water in two containers with the same height but different bottoms dimensions will have the same pressure at the bottom no matter what the shape of the container. (Correct Answer) C. Pressure, when transmitted to a confined amount of water, is greatest in the direction of gravity. D. In two containers with the same bottom dimensions and both containing water, but with unequal heights, the pressure of the water at the bottom of each container is still equal. E. The pressure of a liquid in an open container is proportional to the density of the liquid. (Correct Answer) Types of Pressure - correct answer 1. Atmospheric Pressure (Sea Level 14.7 psi)
- Head Pressure
- Static Pressure
Normal Operation Pressure = Water pressure in a distribution system during normal consumption Knowledge Check 5 Identify THREE Correct statements about pressure - correct answer A. Head pressure is about one third of head height B. Static pressure is usually greater than normal operating pressure (Correct Answer) C. Normal operating pressure is usually measured with a pitot tube an gauge D. Residual pressure is measured near a flowing hydrant (Correct Answer) E. Atmospheric pressure at 10,000 feet is less than 10 psi (Correct Answer) Friction Loss - correct answer Control Valves = water molecules rub against the inside surface of the valves Hoses and Couplings = Hose Friction loss included the hose lining and any couplings. The smoother the hose lining or surface, the less the loss. Couplings contribute to friction loss by rubbing against water molecules. Bend = Water flow is forced to change direction Friction Loss Water Flow Rate, GPM - correct answer IF the water flow rate (GPM) doubles, friction loss is four times greater (2² = 4); if GPM triples, friction loss is nine times greater (3² = 9), and so on hose with a GPM of 100 and a friction loss of 10 psi, if the GPM doubles to 200 GPM, then the friction loss (2²) is four times the original friction loss, or 40 psi.
Friction Loss Hose Diameter - correct answer As hose diameter increases, friction loss decreases - and vice versa, as hose diameter decreases, friction loss increases. Knowledge Check 6 All of the following statements about friction loss are true EXCEPT: - correct answer A. The single greatest factor affecting friction loss is hose diameter. B. Smaller diameter hoses will require higher velocities to flow the same rate as larger diameter hoses. C. If a hose is pumping at 150 GPM with a friction loss of 20 psi, and the flow rate is increases to 300 GPM, the friction loss will then be 80 psi. D. As hose length increases, friction loss decreases. (Correct Answer) Knowledge Check 7 Identify TWO correct statements about water supply and distribution systems - correct answer A. Dead-end hydrants are supplied with water from only one direction. (Correct Answer) B. There are two types of distribution systems vales, VIP and SY&O C. When using private, dual systems, it's important to avoid backflow into nonpotable water sources. D. Valves are placed strategically in a distribution system for quick isolation of problems areas. (Correct Answer) E. An elevated water storage tank is the main water supply for most combination distribution systems.
- Fog Stream = up to 350 GPM at 100 psi
- Broken Stream = up to 350 GPM at 100 psi Fog Nozzles - correct answer 1. Constant Flow = 75 -100 psi
- Manually Adjustable Nozzle = 100 psi
- Automatic Nozzle = 100 psi
- High-Pressure Fog Nozzle = 8-15 GPM, up to 800 psi Special Purpose Nozzles - correct answer Cellar Nozzle = Pushed through a hole in a basement or attic Piercing Nozzle = Steel-tipped rod driven through building walls with a sledge hammer. Chimney Nozzle = Steel cone on a booster hose that is lowered down the flue of a chimney. Knowledge Check Match each nozzle with its correct characteristic
- Breaks water into droplets for quick heat absorption
- Produces a compact stream with little spray
- May look like a good stream but may not be flowing adequate GPM
- Driver/Operator and firefighter should closely coordinate this one
- Used to flight wildland fires - correct answer Fog Stream = 1 High-Pressure = 5
Solid Stream = 2 Automatic = 3 Manually Adjustable = 4 Master Stream Devices - correct answer Monitor Device = Unique in that you can adjust its vertical and horizontal direction while discharging a fire stream. There are three basic types of monitor devices: Fixed, portable, combination type. Deluge Set Device = Cannot change the direction and angle of the fire stream during discharge. it has a short length of large diameter hose with a large nozzle or playpipe supported at its discharge end by a tripod. Turret Pipe Device = Deck gun. It is connected directly to the pump through permanent piping. Elevated Master Stream Device = Large-capacity nozzle mounted on the end of the aerial apparatus elevating device. Knowledge Check Match each nozzle with its correct characteristic.
- Direction and angle can be changed during discharge of water
- Cannot be moved laterally during discharge
- Uses a broken stream for fire suppression
- Often called a deck gun
- Mobile attack line - correct answer Hand Line = 5
Example: Flow rate of 300 GPM and a nozzle pressure of 100 psi. NR = (0.0505) (125) (√100) NR = 63.13 lbs Knowledge Check The counter force to the forward velocity of the water being discharged from a nozzle is known as: - correct answer A. Nozzle reaction (Correct Answer) B. Nozzle pressure C. Nozzle Velocity D. Discharge Pressure Pressure Calculation Formulas - correct answer PDP = NP + TPL NP = 100 psi for hand line fog nozzle NP = 50 psi for hand line solid stream nozzle NP = 100 psi for master stream fog nozzle NP = 80 psi for master stream solid stream nozzle TPL = FL + EP + APL FL = C x (Q/100)² x (L/100) GPM = 29.7 x (d)² x √NP Q = GPM/
Q = (29.7 x (d)² x √NP/ L = Length in feet / 100 EP = 0.5 x H EP = 5 x (Number of floors -1) APL = 10 psi for each appliance with a flow of 350 GPM or greater APL = 25 psi for all master stream devices regardless of flow FL total for wyed hoselines of equal length FL (supply line) + FL (one attack line) TPL = FL (Supply line) + FL (Attack Line) + EP + APL (Wye) Q (attack line 1) = GPM/ Q (attack line 2) = GPM/ Q (Supply) = Q (attack line 1) + Q (attack line 2) FL (Supply Line) = C x (Q (Supply))² x L/ FL total for slamese hoselines of equal length FL (slamesed lines) + FL (attack line) TPL = FL (Siamesed Lines) + FL (Attack Line) + EP + APL (Siamese) Q (siamesed line) = Q (attack line) = GPM/ FL (Siamesed Lines) = C (Siamese) x (Q (Siamesed Lines))² x L/ FL (attack line) = C x (Q(attack line))² x L/ FL total for wyed hoselines of unequal length FL (supply line) + FL (attack line with most friction) + EP + APL Master Streams Q(Total) = 29.7 x (d)² x (√NP) / 100
Standpipes - Single Hoselines 2 ½ = 0. 4 = 0. 5 = 0. 6 = 0. Siamesed Lines of Equal Length Two 2 ½-inch = 0. Three 2 ½-inch = 0. Two 3 with 2 ½ inch couplings = 0. One 3 with 2 ½ inch couplings, one 2 ½ = 0. Two 2 ½, One 3 with 2 ½ inch couplings = 0. Two 3 with 2 ½ inch couplings, one 2 ½ = 0. Friction Loss Practice 1 Flowing 500 GPM through 500 feet of 4-inch hose - correct answer FL = C Q² L FL = C x (Q/100)² x (L/100) FL = 0.2 x (500/100)² x (500/100) FL = 0.2 x (5)² x 5 FL = 0.2 x 25 x 5 FL = 25 Friction Loss Practice 2 Flowing 250 GPM though 500 Feet of 2 ½ inch hose - correct answer FL = C Q² L FL = C x (Q/100)² x (L/100)
FL = 2 x (250/100)² x (500/100) FL = 2 x (2.5)² x 5 FL = 2 x 6.25 x 5 FL = 62. Friction Loss Practice 3 Flowing 200 GPM though 300 Feet of 2 inch hose - correct answer FL = C Q² L FL = C x (Q/100)² x (L/100) FL = 8 x (200/100)² x (300/100) FL = 8 x (2)² x 3 FL = 8 x 4 x 3 FL = 96 Knowledge Check Your fire crew pulls out 400 feet of 3-inch hoseline with 2 ½ couplings. At the pumper, you set the flow rate at 300 GPM. Based on this information, what is the friction loss? - correct answer A. 32.0 psi B. 9.6 psi C. 24.4 psi D. 28.8 psi (Correct Answer) FL = C Q² L FL = C x (Q/100)² x (L/100) FL = 0.8 x (300/100)² x (400/100) FL = 0.8 x (3)² x 4
C. Add 25.8 to the PDP D. Subtract 25.8 from the PDP EP = 0.5 x H EP = 0.5 x 75 EP = 37.5 psi Loss Knowledge Check Your crew is fighting a basement fire in a three-story multi-unit condominium. To account for the elevation pressure, the adjustment you must make to the PDP is to:
- correct answer A. Add 0.5 psi to the PDP B. Subtract 0.5 from the PDP C. Add 5 psi to the PDP D. Subtract 5 from the PDP (Correct Answer) Example Your Crew is fighting a fire on the top floor of a three-story building located at the top of a 20-foot hill. The fire is located in the hallway; your crew is fighting this with a 600-foot hoseline composed of 400 feet of 3-inch hose reduced to 200 feet of 1 ½ inch hose with a 100 GPM fog nozzle. - correct answer FL for 400 feet of 3-inch hose flowing 100 GPM FL = C x (Q/100)² x (L/100) FL = 0.8 x (100/100)² x (400/100) FL = 0.8 x (1)² x 4 FL = 0.8 x 1 x 4 Fl = 3.2 psi Loss
FL for 200 feet of 1 ½ inch hose flowing 100 GPM FL = C x (Q/100)² x (L/100) FL = 24 x (100/100)² x (200/100) FL = 24 x (1)² x 2 FL = 24 x 1 x 2 FL = 48 psi Loss FL = 3.2 + 48 FL = 51. EP for 20-foot Hill EP = 0.5 x H EP = 0.5 x 20 EP = 10 EP for 3rd floor EP = 5 x (FL - 1) EP = 5 x (3 - 1) EP = 5 x 2 EP = 10 EP = 10 + 10 EP = 20 TPL = FL + EP + APL TPL = 51.2 + 20 + 0 (flowing <350 GPM) TPL = 71. PDP = NP + TPL
