NAUI Instructor Course Pre-Qualification Quiz
This is not a “pass” or “fail” exam…this is a get-acquainted quiz. It will allow the course staff to become
acquainted with the enrolling candidate’s knowledge of scuba diving.
Mail (or hand deliver) to:
Fred Calhoun NAUI CD
2 Ocean Ave (1-H)
Magnolia, MA 01930
1-978-525-3432
01 - By law, scuba cylinders must be visually inspected:
a - every year
b - every three years
c - every four years
d - every five years
02 - Common sense practice dictates that scuba cylinders be filled slowly to:
a - 10% less than rated pressure
b - 5% less than rated pressure
c - rated pressure
d - 10% more than rated pressure
03 - The most desirable scuba cylinder:
a - can be filled to 5000psig
b - is of a comfortable size
c - is at least a so-called “80”
d - provides the greatest amount of air possible
04 - The most important feature of a swim fin is:
a - how comfortable it is
b - its power-to-blade-size ratio
c - the presence of power vents
d - whether it floats
05 - Scuba cylinders must be hydrostatically pressure tested:
a - every two years
b - every three years
c - every four years
d - every five years
06 - Of the range of depths listed, where is proper ballasting the most difficult to achieve?
a - between the surface and ten feet
b - between ten feet and twenty feet
c - between twenty feet and thirty feet
d - between thirty feet and forty feet
07 - How much does 80 cubic feet of air weigh?
a - about 6 pounds
b - about 7 pounds
c - about 8 pounds
d - about 9 pounds
08 - Use the U.S.Navy dive tables…
A dive to 67 feet with a bottom time of 32 minutes is followed by a correct ascent procedure. After a
surface interval of 38 minutes, a second dive is made to 76 feet with a bottom time of 22 minutes.
a - What stage decompression is required?
b - What is the group designation following dive #1?
c - What is the group designation following the surface interval?
d - What is the group designation following dive #2?
e - What is the maximum bottom time of the second dive which will not require stage decompression?
09 - Use the U.S.Navy dive tables…
A dive to 76 feet with a bottom time of 22 minutes is followed by a correct ascent procedure. After a
surface interval of 38 minutes, a second dive is made to 67 feet with a bottom time of 32 minutes.
a - What stage decompression is required?
b - What is the group designation following dive #1?
c - What is the group designation following the surface interval?
d - What is the group designation following dive #2?
e - What is the maximum bottom time of the second dive which will not require stage decompression?
10 - While ascending in the water using scuba, a diver must:
a - not ascend faster than his or her smallest bubbles
b - maintain neutral buoyancy
c - never hold his or her breath
d - monitor all diving gauges and instruments
11 - Sport scuba diving is not recommended beyond a depth of:
a - 90 feet
b - 110 feet
c - 130 feet
d - 150 feet
12 - The _____ space between a mask face plate and a diver’s eyes improves a diver’s underwater vision.
13 - A _____ valve is a one-way exhaust valve for clearing water out of a mask.
14 - A most effective signaling device for use at the surface is a _____.
15 - As one inhales, air enters the nose and or mouth and flows down the _____, divides into the bronchial
tubes , and fills the _____.
16 - The exchange of gases in the lungs is called _____.
17 - During a descent, pressure differentials across the various air spaces in and upon a diver’s body may
cause _____.
18 - A breath holding diver (not a scuba diver), free diving below 100 feet, may experience _____ squeeze.
19 - When fully inflated the average adult lungs are about _____ pints big.
20 - Mask squeeze is relieved by admitting _____ through the _____ into the mask.
21 - The middle ear space can be equalized by admitting air through the _____ tube.
22 - An injury caused by pressure is called a _____.
23 - Absolute pressure is the sum of _____ pressure and _____ pressure.
24 - When ascending, a diver should look up, turn 360 degrees, hold one hand up, and _____ at 10 feet.
25 - Hyperventilation is dangerous because it lowers the natural tendency to breathe by lowering the tension
of _____ in the blood.
26 - The density of a substance is its mass (or _____ ) per unit volume.
27 - Archimedes Principle states that a body wholly or partially immersed in a liquid is buoyed up by a
force equal in magnitude to the _____ of the liquid displaced.
28 - Archimedes Principle is the principle of _____ .
29 - Pressure is _____ per unit area.
30 - Atmospheric pressure at sea level may be written as _____ psi.
31 - Another way to describe the barometric pressure at sea level is to call it “one _____”.
32 - In 33 feet of sea water the total pressure is _____, and the gauge pressure is _____.
33 - At a depth of 99 feet of sea water the absolute pressure is _____.
34 - Underwater vision is affected by _____, a phenomenon which occurs when light travels from one
medium to another medium.
35 - Water pressure in the ocean increases by one atmosphere for every ____ feet (about) of depth.
36 - Light travels _____ in water than in air.
37 - The word “ambient” means _____.
38 - The weight of a cubic foot of sea water is about _____.
39 - Salt water weighs slightly _____ than fresh water.
40 - Sound travels _____ times faster in water than in air.
41 - Underwater, when viewed through a flat port diving mask, objects appear _____ than they actually are.
42 - According to Boyle’s Law, when the pressure on a free gas is doubled, what happens to its following
characteristics?
a - its weight is _____,
b - its volume is _____,
c - its density is _____.
43 - A rough but useable “rule-of-thumb” is that the pressure of the air in a full or nearly full scuba cylinder
(say a 3000psig “aluminum 80”) increases or decreases by about _____ psi for every Fahrenheit degree rise
or fall in its temperature.
44 - The solubility of a gas in a liquid is directly proportional to the pressure of that gas over the liquid.
This statement describes _____ Law.
45 - When a liquid has absorbed all the gas that it can absorb at a particular pressure and temperature it is
said to be _____.
46 - The percentage of oxygen in air is about _____.
47 - The partial pressure of oxygen in air at a pressure of two atmospheres is about _____psi.
48 - If a scuba cylinder contains air at a pressure of 2500psig and a temperature of 90 degrees Fahrenheit
what will be its approximate pressure if the temperature of the air is lowered to 75 degrees Fahrenheit?
49 - A balloon contains 2 pints of air and is at a depth of 66 feet of sea water. If this balloon is free to
expand, and survives being brought to the surface, about how many pints of space will it occupy?
50 - What is the approximate partial pressure of nitrogen in air (in psia) inhaled at a depth of 99 feet of sea
water?
51 - If the pressure of a mixture of gases is increased, the partial pressure of the individual gases will _____.
52 - The symbol stamped on a steel cylinder, which allows for a 10% over-fill, is a _____.
53 - A simple on-off valve on a scuba cylinder is called a _____ valve.
54 - A preset spring reserve mechanism valve, used on a scuba cylinder, is called a _____ valve.
55 - A demand regulator delivers air to a diver at _____ pressure.
56 - The diaphragm in a demand type scuba regulator is activated when the diver _____.
57 - The first stage regulator valve, not affected to a great degree by the change of pressure of the air in the
scuba cylinder, is called a/an _____ valve.
58 - True or false: the position underwater of a demand regulator’s second stage with respect to the position
underwater of a diver’s lungs, has no effect on the regulator’s relative ease or hardness of breathing. _____
59 - Currently, wet suits are typically fabricated from _____ neoprene.
60 - Recreational scuba divers use _____ circuit breathing equipment.
61 - When discussing scuba regulators, the term “stages” refers to the number of times that the high
pressure gas in the cylinder is _____ in pressure before it is inhaled.
62 - The maximum pressure to which a cylinder with the following markings (3AA 2250, 12-98 +)may be
filled is _____.
63 - When hydrostatically pressure testing a 3000psig rated scuba cylinder, to what internal pressure is it
subjected?
64 - The air in the hose of a functioning single hose regulator is at a pressure of about _____.
65 - The safest way to “buddy breathe” is with a/an _____.
66 - Properly ballasted scuba divers tend to _____ at the surface.
67 - When diving in salt water, a diver will require _____ weights than when he or she is diving in fresh
water.
68 - The proper ascent rate according to the U.S.Navy is _____ per minute.
69 - What is the treatment for “the bends”?
70 - While underwater conducting an open water class one of your students seems nervous and indicates
that he wants to surface. You should:
a - hold him at the bottom
b - try to relax him, but if he persists move him to the ascent line and go up with him
c - try to keep him on the bottom while you work with the other students
71 - You are conducting a class on emergency ascents. You have three students on the bottom. You are at
the surface working with the fourth student. The student you are working with becomes unconscious on the
surface. You should:
a - establish buoyancy for him and go down and get the other students
b - begin artificial respiration, stay in place at the surface, wait for the other students to come up
c - begin artificial respiration and immediately begin to move towards shore
72 - What first aid treatment is recommended for the bends?
73 - You are teaching a student to clear his mask in deep water. He will not remove his mask. You should:
a - insist that he remove the mask (by gestures and/or writing slate)
b - go to the next student and then come back to him
c - try to coax him to do it
74 - How do you prevent the bends?
75 - Your surface air consumption (when using a particular scuba cylinder) has been determined to be
25psig per minute. In 99 feet of sea water, all other things being equal, what will be the rate?
76 - Define “bottom time”.
77 - If, during a dive, you find that water makes its way into your scuba regulator mouthpiece you should
suspect that you have a leaky _____.
78 - What do the initials “DOT” stand for?
79 - Steel cylinders should have what kind of finish on the exterior of the metal?
80 - The second stages of most single hose regulators have _____ buttons.
81 - Most waves are caused by _____.
82 - A diver on land has a scuba cylinder filled with air to a pressure of 3000psig at a temperature of 80
degrees Fahrenheit. The diver enters the water which is at a temperature of 50 degrees Fahrenheit. What
will be the gauge pressure of the air in the cylinder after it has cooled to 50 degrees Fahrenheit?
83 - At a depth of 66 feet of sea water, a diver attaches a lift-bag to a sunken anchor and fills it to a volume
of 2 cubic feet. What buoyant force will the lift bag exert at that depth?
84 - Nitrogen causes what two diving diseases?
85 - Which gas causes inert gas narcosis?
a - Oxygen
b - Nitrogen
c - Carbon Dioxide
86 - Nausea and twitching muscles are symptoms of which diving disease?
87 - Panting and cyanosis are symptoms of which diving disease?
88 - Cherry red coloring of the mucous membrane is a symptom of which diving disease?
89 - Oil vapor fumes:
a - form a coating on the lungs
b - are colorless and odorless
c - are of little concern to divers above a depth of 33 feet
90 - Your first dive is to 58 feet for a bottom time of 25 minutes. After a surface interval of 4 hours, how
long can you dive to the same depth and not require stage decompression? _____
91 - Your first dive is to a depth of 46 feet for a bottom time of 63 minutes. How long must your surface
interval be before you can repeat the dive and not require stage decompression?
92 - In 90% of the cases of the bends, the principal symptom is _____.
93 - True or false; while decompressing at a depth of 10 feet you should exercise to hasten the elimination
of nitrogen. _____
94 - Without looking at a set of U.S. Navy dive tables, list the no-decompression limits for the following
depths:
60 feet _____, 70 feet _____, 80 feet _____, 90 feet _____, 100 feet _____, 110 feet _____, 120 feet ____
95 - Should divers make adjustments to the U.S. Navy dive tables when diving in fresh water? _____
96 - What is an air embolism?
97 - How much does a cubic foot of “standard air” weigh? _____
98 - How many groups of accessory sinuses of the nose are there in the human head? _____
99 - From how shallow a depth does one have to ascend in order for air embolism to be possible? _____
100 - What is the first organ to receive oxygenated blood flowing from the heart?
101 - How many lobes do the lungs have? _____
102 - A person is unconscious, not breathing and bleeding profusely. You should first:
a - administer oxygen (assuming that it is available)
b - stop the bleeding
c - administer mouth-to-mouth resuscitation
103 - Air embolism can only be treated by _____.
104 - Dizziness, the result of the lowering of the temperature of the air in the middle ear space due to
expansion during an ascent, has been given the name of _____.
105 - For air breathing scuba divers how is nitrogen narcosis prevented?
106 - Explain the dangers of wearing ear plugs while diving.
107 - At a depth of 132 feet of sea water you are under an absolute pressure of about 5 atmospheres. How
deep would you have to descend in fresh water in order to be under about the same absolute pressure?
_____.
108 - You spend 65 minutes working a search pattern between the depths of 20 feet and 35 feet. Upon
surfacing, it takes 15 minutes to change to a full scuba cylinder and begin a second dive. The second dive is
between the depths of 35 feet and 50 feet. The second dive’s bottom time is 43 minutes. Is any
decompression required following the second dive? _____ If the answer is “yes”, what decompression is
required?
Name ________________________________________________________
Address _______________________________________________________
City __________________________________ State ____ Zip ___________
Telephone Number 1-(____) - ____ - ______ Date _____________________
Grade (number of correct answers divided by 108) = _____.