UTA9 Duct and Ventilation Systems Flashcards
You must consider three factors for a water source: quantity, quality, and what else? (Page 9-1)
Reliability
Water sources developed for military use are referred to as what? (Page 9-1)
Water points
The rate of flow, resulting from a given pressure difference, depends on the fictional resistance to flow developed in the formation. The term used to describe this characteristic of a porous material is what? (Page 9-2)
Permeability
The pump and power unit used for testing a well should be capable of continuous operation at a constant and variable rate of pumpage for a period of over how long? (Page 9-3)
24 hours
The most accurate way to measure depth to the static level and to the pumping level in a well is with a what? (Page 9-4)
Chalked tape
The quality of water is the ability of water to be potable and what else? (Page 9-5)
Palatable
Impurities in water are either suspended or what else? (Page 9-5)
Dissolved
The title to ground and surface water in the United States is usually regulated at what level? (Page 9-7)
State
For normal field water supply, what is the most accessible type of water source? (Page 9-7)
Surface water
Moisture is held beneath the surface of the earth in how many zones? (Page 9-10)
Three
Springs yielding how many gallons per minute or more of water can be used as a source of field water supply if properly developed? (Page 9-10)
20
When ground and surface water supplies are inadequate or cannot be used, ground water sup- plies are developed by constructing what? (Page 9-11)
Wells
Wells are classified into how many types, according to their method of construction? (Page 9-11)
Five
A dug well is a large diameter well, seldom less than how many feet in diameter, excavated with hand tools, and lined with brick, stone, steel, wood cribbing, or tile? (Page 9-11)
3
What type of wells are constructed in soft water bearing formations that will not cave in while the hole is being bored? (Page 9-11)
Bores
What type of wells are suitable in soft, unconsolidated, alluvial deposits? (Page 9-11)
Jetted
What type of well is constructed by driving a pointed screen, or drive point, and attached pipe directly into a water-bearing formation? (Page 9-12)
Driven
Drive point wells usually range in diameter from 1 1/4 to 2 inches, but larger sizes up to how many inches also are made? (Page 9-12)
4
Approximately how many cubic feet of snow is required to yield
1 cubic foot of water? (Page 9-13)
5
What is a muddy or unclear condition of water caused by particles of sand, clay, or organic matter being held in suspension? (Page 9-15)
Turbidity
What is the most common method of determining proper coagulant dosages? (Page 9-15)
Jar test
What is the most widely used single process for taste and odor removal in water? (Page 9-16)
Activated carbon
What controls tastes and odors caused by small living organisms in water? (Page 9-15B)
Copper sulfate
The most important chemical characteristics of water are its acidity, alkalinity, hardness, and what else? (Page 9-16)
Corrosiveness
What is undesirable because it imparts a rusty color and objectionable taste to water? (Page 9-17)
Iron
The total concentrations of iron and manganese in potable water should not exceed how many ppm? (Page 9-17)
0.3
What is the term used to identify the process of treating water supply hardness? (Page 9-17)
Water softening
What used in water softening are complex compounds of sodium, aluminum, and silica which have the faculty of exchanging bases? (Page 9-17)
Zeolites
A carbon dose of how many ppm removes most tastes and odors from water? (Page 9-19)
3
Chemical agents are classified in how many categories? (Page 9- 20)
Seven
The ROWPU will successfully remove what percent of CBR contamination from a water source? (Page 9-22)
99
The CBR cylinder filters are capable of decontaminating water for up to how many operating hours? (Page 9-22)
100
In areas where a satisfactory freshwater source cannot be located and existing water treatment facilities are not usable, what process can be used to obtain fresh drinking water from brackish water, seawater, or water containing excessive amounts of dissolved solids? (Page 9-23)
Distillation
The process whereby latent heat is removed and steam becomes water is called what? (Page 9-23)
Condensation
The ROWPU used by the NCF is capable of producing 600 gph of product water from freshwater sources and 400 gph of product water from seawater at what temperature? (Page 9-26)
70°F
Maximum operating water temperature of the ROWPU feedwater is what? (Page 9-26)
120°F
What is a purification process in which filtered water is pumped against a semipermeable membrane under great pressure? (Page 9- 26)
Reverse Osmosis (RO)
The simplest form of water filter is the what? (Page 9-27)
Sand filter
Properly operated diatomite filters are capable of removing from coagulated and settled water, amoebic cysts, the cercariae of schistosomes, and approximately what percent of the bacteria? (Page 9-28)
90
What is the most commonly used chemical for disinfection of water? (Page 9-30)
Chlorine
Chlorine demand in most water is likely to be largely satisfied how many minutes after chlorine is added? (Page 9-31)
10
What is a quick means of disinfecting small quantities of water in the field by individual soldiers? (Page 9-32)
Boiling
What is the application of chlorine to produce a residual of free available chlorine with no combined chlorine present? (Page 9-32)
Breakpoint chlorination
What is the application of more chlorine than needed for the chlorine residual essential to marginal chlorination? (Page 9-32)
Superchlorination
It is now illegal to use what type of material for making ducts?
Asbestos
(True or False) The first step to follow, when sizing a duct systems, is to calculate the air volume required for heating and cooling the required space.
True
What air balancing instrument can be permanently connected to duct interiors using static pressure tips?
Manometer
(True or False) When balancing a duct system, the first step is to determine the type of fan that is being used in the system.
True
How many ventilation air changes are considered the minimum for a residence during the heating season?
3 changes every hour
(True or False) Hospitals use positive air pressure and require a 75- percent fresh air intake.
False
100 percent fresh air intake
The velocity of a high-pressure duct system is usually limited to how many feet per minute (fpm)?
4,000 FPM
The velocity of a low-pressure duct system is generally less than how many feet per minute (fpm)?
2,000 FPM
What type of material is used to make duct systems?
A. Galvanized sheet steel
B. Fiberboard
C. Aluminum sheets
D. All of the above
D. All of the above
(True or False) Rectangular ducts usually have the advantage of saving room space and are easier to install in walls.
True
What type of duct system allows individual room conditions to be maintained from a central system, by blending hot and cool air through automatically controlled mixing devices?
Double duct system
(True or False) Fiber glass duct constructed of molded-glass fibers should never be coated with vinyl or other plastic coatings.
False
What air balancing instrument indicates air pressure by employing the principle of balancing a column of liquid of know weight against air pressure?
Manometer
(True or False) The third step for duct system balancing preparation is to obtain data pertinent to motors, fans, diffusers, and grilles that are not given on drawings.
True
When balancing a duct system, what balancing instrument, along with a pressure probe, can be used to determine fan static pressure?
Velometer
(True or False) Certain areas of a building, such as hallways and bedrooms, should have a slightly less positive pressure to reduce the spread of odors.
False
Kitchens
Lavatories
Industrial environments that produce fumes
What type of blower can be used to provide more air movement when heating and cooling systems have been turned off?
Variable-speed blowers
What type of gravity ventilator may be roof-mounted? A. Stationary B. Pivoting wind-directional C. Rotating-turbine D. All of the above
D. All of the above
To deliver air to the conditioned space, you need air carriers. These carriers are called what? (Page 13-1)
Ducts
Systems with velocities more than how many fpm peforms satisfactorily when all duct fittings are carefully designed and installed? (Page 13-1)
4,000
The term low-pressure or low-velocity duct- work applies to systems with fan static pressures less than 3 inches WC. Generally, duct velocities are less than how many feet per minute? (Page 13-2)
2,000
Ducts made of what material are no longer legal? (Page 13-3)
Asbestos
All duct elbows, including supply, exhaust, and return, should be made with a center line radius of how many times the duct width, parallel to the radius wherever possible? (Page 13-5)
1.5
Fiber glass meets military specifications for a flame spread rating of less than 25 and a smoke development rating of less than 50 for insulating material. The thickness of fiber glass ducts allowed for use in Navy installations must range between 3/4 inch to how many inches, depending upon the size of the duct? (Page 13-7)
2
Unless aluminum surface duct is used, the specification of the duct should be checked carefully to ensure that it does not fail when heated over what temperature? (Page 13-7)
250°F
What is a measure of the outward push of air on the walls of a duct? (Page 13-10)
Static pressure
In most problems concerning duct systems, air pressure is expressed in terms of inches of water (1 pound per square inch = how many inches of water?) (Page 13-11)
27.74
There are four measuring devices used with the basic meter for determining air velocities and pressures. They are the pitot probe, low flow probe, diffuser probe, and what else? (Page 13-11)
Static pressure probe
Normally air contains about what percent oxygen? (Page 13-16)
21