Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
89 Cards in this Set
- Front
- Back
What is the most commonly used fire extinguishing agent? |
Water
|
|
Below what temperature does what exist in a solid form?
|
32 ℉
|
|
Water is it’s heaviest close to it’s ________ ______, and lightest close to its _______ ______.
|
Freezing point; boiling point
|
|
Ordinary fresh water is generally considered to weigh?
|
62.5 lb/ft3 or 8.33 lb/gal
|
|
A measure of the heat-absorbing capacity of a substance.
|
Specific Heat
|
|
Between 32℉ an 212℉ water exists in what state?
|
Liquid
|
|
Above what temperature does water covert to Gas?
|
212 ℉
|
|
The primary way water extinguishes is by _______.
|
Cooling
|
|
Specific gravity determines whether water will do what on the surface on another liquid, or visa versa?
|
Float
|
|
The amount of heat required to raise the temperature of one pound of water 1℉.
|
Specific heat
|
|
The specific Heat of a substance is a ratio between what two things?
|
The heat needed to raise the temperature of a specified quantity of a material and the heat needed to raise the temperature of an identical amount of water the same number of degrees.
|
|
The temperature at which a liquid absorbs enough heat to change to vapor.
|
Boiling Point
|
|
At 212℉ water expands how many times its original volume?
|
1,700 times
|
|
Water absorbs ____ times as much heat as does an equal amount of carbon dioxide.
|
five
|
|
The specific gravity of water.
|
1
|
|
The quantity of heat absorbed by a substance when it changes from liquid to a vapor.
|
Latent heat of Vaporization
|
|
Vaporization does not completely occur when water reaches 212℉, each pound of water requires an additional ______ of heat to completely convert into steam.
|
970 BTU
|
|
The speed with which water absorbs heat increases in proportion to what?
|
The water surface area exposed to the heat.
|
|
The tendency of a liquid to possess internal resistance to flow.
|
Viscosity
|
|
The density of a liquid in relation to water.
|
Specific gravity
|
|
A force per unit of area.
|
Pressure
|
|
Weight of one cubic foot of water?
|
62.5 pounds
|
|
The speed at which this fluid travels through a hose.
|
Velocity
|
|
Fluid pressure at a point in a fluid at rest is the same intensity in all directions.
|
Second Principle of Pressure
|
|
The pressure of a liquid in an open vessel is proportional to its depth.
|
Fifth Principle of Pressure
|
|
A simple measure of of weight and is usually expressed in pounds or kilograms.
|
Force
|
|
1 inch3 by 1 ft tall exerts a pressure of what at it’s base?
|
0.434 lbs
|
|
Fluid pressure is perpendicular to any surface on which it acts.
|
First Principle of Pressure
|
|
Pressure applied to a confined fluid from without is transmitted equally in all directions.
|
Third Principle of Pressure
|
|
The pressure of a liquid in an open vessel is proportional to the density of the liquid.
|
Forth Principle of Pressure
|
|
Mercury is __.__ times denser than water.
|
13.55
|
|
At sea level the atmosphere exerts what pressure?
|
14.7 PSI
|
|
At sea level a column of mercury is how tall?
|
29.9 inches tall
|
|
PSIA
|
Pounds per square inch absolute
|
|
Absolute Zero pressure.
|
Absolute Vacuum
|
|
The pressure of a liquid on the bottom of a vessel is independent of the shape of the vessel.
|
Sixth Principle of Pressure
|
|
A pressure of 1psi makes a column of mercury about _.__ inches tall.
|
2.04
|
|
PSIG
|
Pounds per square inch gauge
|
|
Any pressure less than actual pressure.
|
Vacuum
|
|
The fire service refers to the height of a water supply above the discharge orifice as what?
|
Head
|
|
Stored potential energy available to force water through pipe, fittings, fire hose, and adapters.
|
Static pressure
|
|
That pressure found in a water distribution system during normal consumption demands.
|
Normal operating pressure
|
|
The forward velocity flow pressure can be measured by using what?
|
Pitot tube and Gauge
|
|
The center line of the pump or the bottom of a static water supply source above or below ground level.
|
Elevation
|
|
Atmospheric pressure _____ as height above sea level increases.
|
Drops
|
|
Means at rest or without motion.
|
Static
|
|
Part of the total available pressure not used to overcome friction loss or gravity while forcing water through pipe, fittings, fire hose and adapters.
|
Residual Pressure
|
|
Forward velocity pressure at a discharge opening while water is flowing.
|
Flow Pressure
|
|
The position of an object above or below sea level.
|
Altitude
|
|
Above sea level, atmospheric pressure decreases approximately _._psi for every ____ft.
|
0.5psi ; 1000ft
|
|
Both pressure loss and pressure gain are referred to as What?
|
Elevation pressure
|
|
The friction loss in old hose may be as much as ___ greater than in new hose.
|
50%
|
|
For the same discharge, friction loss varies inversely as the fifth power of the diameter of the hose.
|
Third Principle of Friction Loss
|
|
For a given flow velocity, friction loss is approximately the same, regardless of the pressure on the water.
|
Fourth Principle of Friction Loss
|
|
When the diameter of the hose doubles, the area of thee hose opening increases approximately ____ times.
|
Four
|
|
The total pressure lost while forcing water through pipe, fittings, fire hose, and adapters.
|
Friction loss
|
|
If all other conditions are the same, friction loss varies directly with the length of the hose or pipe.
|
First Principle of Friction Loss
|
|
When hoses are the same size, friction loss varies approximately with the square of the increases in the velocity of the flow.
|
Second Principle of Friction Loss
|
|
With water being virtually incompressible, it requires _____psi to reduce it’s volume by 1%.
|
30,000 psi
|
|
When the velocity or speed of a stream increases beyond it’s practical limits and the friction becomes so great it causes agitation or turbulence.
|
Critical Velocity
|
|
What three characteristics of hose layouts cause friction loss?
|
- Hose length
-Hose diameter -sharp bends (kinks) in the hose |
|
Suddenly stopping water moving through a hose or pipe results in and energy surge being transmitted in the opposite direction. This surge is referred to as what?
|
Water Hammer
|
|
Three methods of moving water in a system.
|
-direct pumping system
-Gravity system -combination system |
|
When a fire hydrant receives water from two r more directions is said to have a what?
|
Circulating Feed
Or Looped Line |
|
Large pipes, with relatively widespread spacing, that convey large quantities of water to various points of the system for local distribution to the smaller mains.
|
Primary feeders
|
|
Realistically, a hose larger than _inches in diameter cannot be used for handlines.
|
3 inches
|
|
What are the four fundamental components of a Water system?
|
-Source of water supply.
-Means of moving water. -Water processing or treatment facility. -Water distribution system, including storage. |
|
Afire hydrant that receives water from only one direction.
|
Dead-end Hydrant
|
|
A distribution system that provides circulating feed from several mains.
|
Grid System
|
|
Grid arrangement of smaller mains serving individual fire hydrants and blocks of consumers.
|
Distributors
|
|
In residential areas there should be cross connecting mains at intervals of not more than what?
|
600 ft
|
|
What size mains should be used on principle streets and long mains not cross-connected at frequent intervals.
|
12 inch diameter
|
|
Valves for water systems are broadly divided into what two types?
|
Indicating
And Non-indicating |
|
What are the most common valves used on most public water distribution systems?
|
Non-indicating valves
|
|
In residential areas, the recommended size for fire hydrant supply mains is at least what?
|
6 inches in diameter
|
|
In the business and industrial districts, the minimum recommended size is an __ inch main with cross-connecting mains every ___ft.
|
8 inch; 600 ft
|
|
Water mains as large as __inches diameter can be found in major cities.
|
48 inches diameter
|
|
What are two common indicator valves?
|
Post Indicator Valve (PIV)
And Outside Screw and Yoke (OS&Y) |
|
What type of valves will you normally find in a water distribution system, normally installed in valve boxes or manholes?
|
Non-indicating valves
|
|
The average of the total amount of water used in a water distribution system over the period of one year.
|
Average Daily consumption (ADC)
|
|
The maximum amount of water used in any 1-hour interval over the course of a day.
|
Peak Hourly Consumption (PHC)
|
|
The peak hourly rate normally varies from _-_ times the normal hourly rate.
|
2-4 times
|
|
If there is any question about the reliability of a private water supply system or of its ability to provide an adequate amount of water for large-scale fire fighting operation, the department should do what?
|
Make arrangements to augment the private water supply.
|
|
Almost universally, private water supply systems maintain separate piping for what?
|
Fire protection
And Domestic/industrial processes |
|
The maximum total amount of water that was used during any 24-hour interval within a 3-year period.
|
Maximum daily consumption (MDC)
|
|
The maximum daily consumption is normally about _-__ times the average daily consumption.
|
1 - 1½ times
|
|
Private water systems exist for one of what three reasons?
|
-To provide water strictly for fire protection purposes.
-to provide water for sanitary and fire protection purposes. -To provide water for fire protection and manufacturing processes |
|
Where are private water supply systems normally found?
|
Large commercial, industrial, or institutional properties.
Ma be found in some residential developments. |
|
Water pipe that is underground is generally made of what?
|
Cast Iron
Ductile iron Asbestos cement Steel Plastic concrete |