Skin Diving Course Lecture Outline

This section is for the use of those persons who wish to conduct a course in skin diving. This book should be given to every student as a text book, with reading assignments given each session. This lecture outline should be followed closely, with the instructor being sure that all of the points outlined are covered. It is essential that the Progressive Aquatic Training section be used in conjunction with the lecture outline.

Some of the lectures lend themselves very well to demonstrations, some of which are listed. There may be other visual demonstrations that the instructor may wish to utilize, and these need not be complicated. In fact, the simpler the demonstration the more effective. In many instances the simple use of balloons to represent the lungs, or to demonstrate the effects of pressure is very effective. For many more visual type demonstrations, a visit to the local high school physics department, or perusal of a physics text may prove rewarding.

LECTURE #1

I. Brief History of Diving

A. Hard Hat
B. Skin Diver
C. Scuba; Cousteau and Gagnan

II. Equipment

A. Mask
1. Purpose
2. Construction
3. Fit
4. Fogging

B. Fins
1. Purpose
2. Construction
3. Use
C. Snorkel
1. Purpose
2. Use

III. Fundamental Physics

A. Air has weight
1. Demonstration #1
2. Atmospheres

B. Water
1. Salt Water: Column 33' x 1" x 1" equals 14. 7 pounds. Column 1" x 1" x 1 foot equals .445 pounds.
2. Fresh Water: Column 34' x 1" x 1" equals 14.7 pounds. Column 1" x 1" x 1 foot equals .432 pounds.
3. Weight of water; 1 cubic foot:
a. Salt: 64 pounds
b. Fresh: 62.4 pounds

C. Pressures
1. Ambient
2. Absolute
3. Gauge

D. Archimedes Principle

E. Air Components

IV. Fundamental Physiology

A. Respiration; Compare respiration to inverted tree.

B. Circulation
1. Heart a double acting pump.
2. Trace out whole system.

C. Interdependence of two systems.

D. Hyper ventilation
1. Critical carbon dioxide level
2. Anoxia
3. Limits
 
QUIZ ON LECTURE #1

Given at beginning of second class period
1. What are the principle components of air?
2. What is meant by "Atmospheric pressure"?
3. What is the absolute pressure at 34 feet fresh water?
4. What is the gauge pressure at 34 feet fresh water?
5. Simply describe the respiratory system.
6. Simply describe the circulatory system.
7. If a body is placed in water and it sinks, it is said to have negative buoyancy. What determines whether it sinks or floats?
8 . What stimulates a person to exhale?
9. Why is a person able to hold his breath longer after hyperventilation?
10. What danger lies in hyperventilation?

LECTURE #2 PROBLEMS ON DESCENT

I. Boyle s Law

A. State Formally, then explain.

B. Demonstration #2

C. Refer to following chart:

Atmosphere      Depth               Volume            Pressure     Px              Vol x
1                      0                      10 pts               14.7           1                1
2                      34' fresh           5 pts                 29.4           2                1/2
3                      68' fresh           3.33 pts            44.1           3                1/3
10                    306' fresh         1 pt                  147.0         10              1/10

11. Squeezes

A. Ear Squeeze
B. Sinus Squeeze
C. Thoracic Squeeze
E. Attached Air Spaces

III. Clearing

IV. Vertigo

QUIZ ON LECTURE #2 Given at beginning of third class period

1. State, in your own words, Boyles Law.
2. Explain the function of the eustachian tubes
3. If a diver free dives to 68' fresh water, what has happened to the volume of his lungs?
4. If a skin diver's lungs contain 10 pints of air at the surface, and he then
descends to 34' fresh water, what is the volume of his lungs at that depth?
5. What is Thoracic Squeeze?
6. Explain how a diver might incur Sinus Squeeze?
7. What is suit squeeze?
8. How does one prevent mask squeeze?
9. What is meant by "clearing" your ears?
10. Explain the term "vertigo".

LECTURE #3 PROBLEMS AT DEPTH

I. Composition of air

11. Dalton's Law

A. Demonstration #3
B. Use table following to demonstrate Dalton's Law.

III.      
Depth               Part. Press        Part. Press of    PSIA                Atmospheres
                        of Oxygen        Nitrogen
0                      2.94                 H.76                14.7                 1
33                    5.88                 23.52               29.4                 2
66                    8.82                 35.28               44.1                 3
99                    11.76               47.04               58.8                 4
297                  *29.4               117.6              147.0               10

*Oxygen poisoning using compressed air in open circuit scuba.

IV. Henry's Law

A. State law, then explain
B. Demonstration #4
C. Nitrogen Narcosis
D. Oxygen poisoning
E. Gas Mixtures

QUIZ ON LECTURE #3 Given at beginning of fourth class period

1. Explain the importance of Dalton's Law.
2. What is the partial pressure of oxygen at 58 feet fresh water?
3. What is the partial pressure of nitrogen at 64 feet fresh water?
4. State, in your own words, Henry's Law.
5. Give two diving ailments which are a direct manifestation of Henry's Law.
6. Give cause, prevention, symptoms, and treatment of Nitrogen Narcosis.
7. Give cause, prevention, symptoms, and treatment of Oxygen Poisoning.
8. Of what use are "gas mixtures" to a diver?
9. Why is a diver breathing an oxy-helium mix still subject to Narcosis, though much reduced?
10. To what should the sport diver limit his depth? Why?

LECTURE #4

PROBLEMS ON ASCENT

I. Review of Henry's Law

11. Bends

A. Cause
B. Symptoms
C. Prevention

D. Treatment
1. Decompression tables
2. Repetitive Dive tables
3. Treatment Tables

III. Air Embolism

IV. Pneumothorax

V. Emphysema

VI. Carbon Monoxide Poisoning

VII. Carbon Dioxide Poisoning

VIII. Anoxia

IX. Vertigo

X. Panic

QUIZ ON LECTURE #4

Given at beginning of fifth class period

1. State Henry's Law in your own words.
2. Explain physiologically, the bends. Include symptoms, cause, prevention, and treatment.
3. Explain physiologically, air embolism. Include cause, prevention, and
treatment.
4. Discuss, as above, pneumothorax.
5. What is the usual cause of Carbon Monoxide poisoning in scuba?
6. What is the most distinctive symptom of Carbon Monoxide poisoning?
7. What is the. most distinctive symptom of Carbon Dioxide poisoning?
8. Where does a diver usually encounter anoxia?
9. Describe the sensation of vertigo, and explain how it is often incurred
by divers.
10. If asked to sum up the way best to avoid succumbing to panic, what would your summation be?

LECTURE #5 SCUBA MECHANICS

I. Closed circuit scuba

A. Breathing Bag
B. Carbon Dioxide Absorbent
C. Function of Unit
D. Carbon Dioxide Poisoning
E. Oxygen Poisoning

II. Open circuit scuba; general function

III. Single stage regulator

A. Diagram regulator in open and closed positions.
B. Explain non-return valves in mouthpiece

IV. Two stage regulator

V. Single hose regulator

VI. K-valve

VII. J-valve

VIII. Depth-compensated reserve

QUIZ ON LECTURE # 5

Given at the beginning of sixth class period

1. Explain the operation of closed circuit scuba.
2. Why is closed circuit scuba not adaptable for sport diving?
3. What is the basic function of open circuit scuba?
4. Describe, in detail, the function of a single stage regulator.
5. Why does a two hose regulator "free flow" when the mouthpiece is raised above the regulator while underwater?
6. Describe the operation of a single hose regulator.
7. Describe a K-valve.
8. Describe the operation of a J-valve.
9. Explain the principle upon which the depth compensated reserve operates.
10. Explain the importance of having a reserve while using scuba.

LECTURE # 6 DIVING SAFETY

I. Mechanical Maintainance

A. Cylinders
B. Regulators
C. Spearguns
D. Masks, fins, suits, inflatable devices.

11. Behavioral Safety

A. From car to dive site
B. Small boat behavior
C. Diver's Flag
D. Buddy System
E. Entries

III. Survival Techniques

A. Buddy Breathing
1. Mouthpiece Shuttle
2. Severed Hose

B. Free Ascent

QUIZ ON LECTURE #6

Given at beginning of seventh class period
1. How often should high pressure cylinders be retested?
2. How would you care for your regulator after a dive?
3. Why should you never bring a loaded speargun above water?
4. When not being used, how should rubber goods be stored?
5. How should your inflatable devices be checked? Why?
6. Of what use is the diver's flag?
7. Why is the buddy system important?
8. If, while diving at depth, your scuba became completely inoperative, what would be your procedure?
9. While ascending buddy breathing, why is it vital to remember to continue to exhale ?
10. What is the most important single act to perform while making a free ascent?

LECTURE #7

MARINE ENVIRONMENT I.

I. Show an underwater film, either fresh or salt water.

11. Frequent hazards

A. Sun
B. Sea Urchins
C. Jelly fish

III. Ecology of predators

IV. Preventive actions regarding predators.

V. Entering and leaving surf

VI. Fresh water diving

VII. Exposure suits

A. Wet suit
B. Dry suit

QUIZ ON LECTURE #7

Given at beginning of eighth class period

1. Explain the theory of the wet suit.
2. Explain the theory of the dry suit.
3. Explain how you would conduct yourself in order not to attract the attention of predators in salt water.
4. What is the greatest hazard to a diver in salt water?
5. If you were to go to an area to dive with which you were completely unfamiliar, what would be a wise procedure?

LECTURE #8

I. Mouth-to-mouth resuscitation

A. Demonstration by Instructor
B. Class practice upon one another
II. Discussion of equipment; have local dealer of equipment or prominent local diver conduct the discussion.

III. General question session by students concerning equipment.

LECTURE #9

REVIEW I.

I. This session should be a guided question and answer session concerning the entire course. The instructor should guide the discussion by asking the students questions when class response lags.

II. The following examinations may be used as a source of final examination questions, or merely as a guide to the student as to the type of knowledge expected.

SAMPLE NO. 1

SKIN AND SCUBA DIVING FINAL EXAM

1. (a) Describe physiologically: Mediastinal Emphysema (2 points)
(b) Cause: (2 points)
(c) Prevention: (2 points)

2. (a) Describe physiologically: Air Embolism (4 points)
(b) Cause: (4 points)
(c) Prevention: (2 points)
(d) Treatment: (2 points)

3. (a) Describe physiologically: "Bends" (4 points)
(b) Cause: (2 points)
(c) Prevention: (4 points)
(d) Treatment: (2 points)

4. (a) Describe Nitrogen Narcosis (2 points)
(b) Cause: (2 points)
(c) Prevention: (2 points)

5. (a) Describe oxygen poisoning symptoms (2 points)
(b) How incurred in diving? (2 points)

6. (a) Define Anoxia (2 points)
(b) How incurred in diving? (2 points)
7. (a) Define ear squeeze (2 points)
(b) Cause: (2 points)
(c) Prevention: (2 points)

8. (a) Explain the function of closed circuit SCUBA (2 points)
(b) Tell its advantages (2 points)
(c) Tell its disadvantages

9. Describe the operation of a single stage regulator (2 points)

10. Describe the operation of a "J", or positive reserve valve. (2 points)

11. Describe the operation of an "R" or restricted orifice. (2 points)

12. Explain, in your own words, Boyles Law (5 points)

13. Give 2 examples of the application of "Boyles Law" in diving. (4 points)

14. Explain, in your own words, Henry's Law of Solubility of gases.

15. Give two examples of the application of Henry's Law in diving (4 points)

SKIN AND SCUBA DIVING FINAL EXAM page 2

16. What are the symptoms of Carbon Monoxide poisoning? (2 points)

17. (a) What is the absolute pressure at 135 feet Fresh Water? (2 points)

(b) What is the gauge pressure at 135 feet Fresh Water? (2 points)

18. If a flexible container with a volume of 4 cubic feet of air at the surface is taken to 238 feet (fresh water), what is its volume at that depth? (2 points)

19. If a flexible container has a volume of 4 cubic feet of air at 170 feet, what will its volume be if brought to the surface? (2 points)

20. A flexible container filled with air is taken to 220 feet (fresh water)

(a) What is the partial pressure of Nitrogen (2 points)
(b) What is the partial pressure of oxygen (2 points)

21. If a set of double "70'sM have 1600 PSI of air in them, how long will they be good for at 136 feet (consumption 1 cu. ft/min at surface) (4 points)

21. ALTERNATE

If a flexible container containing 10 pints of air at the surface is taken to 142 feet (fresh water) what will its volume be at that depth? (4 points)

SAMPLE EXAM NO. 2

Define Symptoms, treatment, cause and prevention of the following diving diseases:

1. Nitrogen Narcosis
2. Air Embolism
3. Carbon Monoxide Poisoning
4. Caisson Disease (bends)
5. Spontaneous Pneumothorax
6. Oxygen Poisoning
7. Carbon Dioxide Poisoning
8. Anoxia
9. What is the accepted rate of ascent in Scuba diving?
10. What is atmospheric pressure? At what depth does the diver reach two atmospheres (Gauge) in fresh water? In salt water?
11. What would the absolute pressure be at 100 feet fresh water?
12. Explain the operation of an open circuit unit; .A closed circuit unit; and/or advantage or disadvantage of each.
13. If an elastic container were filled with 21 pints of air at the surface, at what depth would its volume be reduced to 7 pints in fresh water?
14.If the same container (#13) were filled with 21 pints of air at the surface, what would its volume be at a depth of 26 feet fresh water?
15. What are the basic physical requirements for the prospective skin diver?
16. What is the importance of the following equipment to the SCUBA DIVER, explain them. (A) mask (B) fins (C) weight belt (D) knife
17. Explain in your own words (no formulae) the relationship between pressure and volume, (Boyles Law) and how it pertains to SCUBA diving.
18. Explain, in your own words, the relationship (no formulae) between pressure and solubility of gases in a fluid (Henry's Law).
19. Explain in your own words, (no formulae) the proportion of different gases under pressure. (Dalton's Law)
20. What is the protection theory of the dry suit? The wet suit?
21. Assuming your consumption of air at 1 cu. ft. per minute at the surface, how much time would you have at 68 ft. in fresh water if you had a set of double 70 cu. ft. tanks containing 1800 psi? (use standard 2250 psi as working tank pressure).
22. When breathing air in fresh water, at what depth would you be endangered of Oxygen poisoning?
23. Explain the two methods of popping ears and explain what happens physically.
24. Using compressed air as a media, what would be the partial pressure of Nitrogen at 76 feet in fresh water?
25. You are at 100 feet, and your unit becomes inoperative. What is your procedure for ascent?

SAMPLE EXAM NO. 3 SCUBA FINAL EXAMINATION

1. Why is a person able to hold his breath longer after hyperventilating?
2. What is the main difference between the two stage and the single stage regulator?
3. Describe, in detail, the function of a single stage regulator.
4. What is the partial pressure of Nitrogen at a depth of 163 ft., freshwater? (psia, in air).
5. If a skin diver dives to considerable depth and stays there too long, he may suffer from anoxia on the ascent. Why?
6. State in your own words Boyles Law. (No formulae).
7. Give three examples of diving maladies caused by the effect of Boyles Law.
8. State Henry's Law.
9. Give two examples of Henry's Law in relation to diving maladies.
10. If a diver has 1800 psi in a 70 cubic ft. tank, how long can he dive at 102 feet in fresh water? (Consumption rate 1 cubic ft. / min. at the surface).
11. If you are diving at 50 ft. with scuba and your lung becomes completely inoperative, what would your emergency procedure be?
12. Describe physiologically the disease known as bends. Include in your discussion the cause, prevention, and treatment. Explain what physical law is involved and how it manifests itself.
13. As above, discuss air embolism.
14. Describe the effects, cause, and prevention of Nitrogen Narcosis.
15. Name two ways a scuba diver might incur Oxygen poisoning.
16. Define "Eustachian tube", locate it physiologically, and explain its importance to a diver.
17. Describe in detail a depth compensated reserve, and explain the principle upon which it functions.

SCUBA FINAL EXAMINATION

Page 2.

18. Some objects float, some sink, and some hover in water. These are all examples of Archimedes principle. What is Archimedes principle?
19. If a flexible container contains 5 pints of air at 102 feet fresh water, and is then brought to the surface, what will its volume be at the surface?
20. Define "Mask Squeeze" and explain its prevention.
21. Describe in detail the function of a "J" valve.
22. If your partner contracts carbon monoxide poisoning, what would be the outstanding symptom which would be apparent to you?
23. Some of the old fables tell of heroes, breathing through a long "snorkel" device some 15 feet below the surface of the water. This, of course, is impossible. Why ?
24. What is the danger involved in hyperventilating?
25. You, as a diver, are wearing a wet suit. You weight yourself so that you have neutral buoyancy at 20 feet. As you descend beyond 20 feet you find that you are progressively more negative. Why?
26. What are the primary symptoms of oxygen poisoning?
27. Why is panic a diver's most dangerous foe? If you were asked to give in one sentence, a rule for avoiding panic, what would that rule be?
28. When using scuba, why should a diver carry a snorkel?
29. In Europe the diving tanks are in what we would normally consider an inverted position. That is, the tank valve is down, instead of at the top.

A. Presuming the hoses of a two hose regulator were long enough, how would your regulator function in this position? Why?

B. Presuming the hose of a single hose regulator was long enough, how would it function in this position? Why?

30. If the lung is ruptured and air escapes, where do the air bubbles lodge
in each of the following:

A. Subcutaneous Emphysema
B. Mediastinal Emphysema

SCUBA FINAL EXAMINATION

Page 3.

31. Explain briefly, the difference between decompressing and recompressing.
32. Give the "symptoms" of vertigo, and two possible causes.
33. When a person contracts carbon dioxide poisoning, he has a distinctive
coloration as one of the overt symptoms. What is this color?
34. What is the theory of the wet suit?
35. What is the absolute pressure at 92 feet sea water? (psia).

LECTURE #11 I. Critique of Examination

II. Discussion by instructor or prominent local diver concerning local diving sites and conditions.

III. Discussion by local diving club representative or local Council representative concerning the role of the club and council in sport diving.

It is strongly suggested that the students be accompanied on their first live water dive by an instructor. The psychological advantage this gives the student is inestimable. The initial dive should not be too prolonged, but should be representative of the diving in the area.

CLASSROOM DEMONSTRATIONS DEMONSTRATION #1

MATERIALS NEEDED:

1 gallon varnish can. Small quantity of water. Hot plate.

PURPOSE:

To demonstrate the weight of air.

PROCEDURE:

A small amount of water is placed inside the varnish can, then placed on the hot plate and allowed to boil vigorously. Once it has reached a vigorous boil the can is removed from the hot plate and the cap placed on the can.

RESULTS:

As the can cools it will collapse, due to the fact that the escaping water vapor purged the can of air. As the can cooled the moisture inside the can condensed, thus creating a partial vacuum in the can.

SUMMATION:

This demonstration shows the weight of air in our atmosphere. Since a partial vacuum was created inside the can, the weight of the surrounding air, or in other words, ambient pressure, was greater than the structure of the can could withstand, hence, it collapsed. Prior to the demonstration, the can contained the same pressure inside as out, or in other words, the pressure was equalized and so there was no reaction.

DEMONSTRATION #2 MATERIALS NEEDED:

Combination pressure-vacuum pump. *

Bell jar. *

Two small balloons.

PURPOSE:

To demonstrate the effect of Boyles Law.

PROCEDURE:

Tie the two balloons together at the necks after they have been inflated, to represent human lungs. Place the balloons inside the bell jar and pump pressure inside the jar. When the desired effect has been attained, evacuate the air from the jar until atmospheric pressure has been reached.

RESULTS:

As the pressure inside the bell jar was increased, the volume of the balloons decreased. As the pressure was released until it reached atmospheric pressure, the balloons returned to their original volume.

SUMMATION:

As pressure on the balloons increased, as it does on human lungs as a diver free dives to depth, they decreased in volume. As the pressure returned to atmospheric, the balloons returned to their original volume, just as human lungs do when returning to the surface from a free dive to depth. * Can usually be borrowed from a local school physics department.

CLASSROOM DEMONSTRATIONS DEMONSTRATION #3

MATERIALS NEEDED: Pie pan.

Eight ounce pop bottle, clear glass. Food coloring. Four inch candle.

PURPOSE:

To demonstrate Dalton's Law.

PROCEDURE:

The candle is mounted in the pie pan and the pan filled with water colored with food coloring. The candle is lighted and the bottle up-ended over the lighted candle.

RESULTS:

The candle will burn brightly for a few seconds, then will sputter and go out. As it goes out the colored water will rise in the bottle approximately one fifth of the volume.

SUMMATION:

As the oxygen in the air was consumed by the flame, the pressure formerly exerted by the oxygen was replaced by the rise of the colored water, since there was then a greater pressure being exerted upon the water outside. This demonstration demonstrates that each component gas exerts its own partial pressure independently.

DEMONSTRATION #4

MATERIALS NEEDED:

One bottle of carbonated beverage, clear glass bottle.

PURPOSE:

To give example of Henry's Law.

PROCEDURE:

Explain Henry's Law to class and explain that carbonated beverages are bottled under pressure of carbon dioxide. Shake beverage, showing relatively few bubbles in beverage. Then after displaying, uncap bottle.

RESULTS:

As the bottle is uncapped the beverage will foam out of the bottle, at the same time emitting a "pop" when opened.

SUMMATION:

Because the beverage was bottled under pressure, the fluid contained a large quantity of carbon dioxide in solution. However, when that pressure was rapidly released, the gas came out of solution in the form of bubbles.
CLASSROOM DEMONSTRATIONS DEMONSTRATION #5

MATERIALS NEEDED:

Vacuum pump. *
Bell jar. *
Balloons.
Red food coloring.

PURPOSE:

To simulate air embolism.

PROCEDURE:

Place some red food coloring inside the balloons and inflate them. Tie the balloons together at the neck to simulate human lungs. Place "lungs" in bell jar and evacuate the air until the swelling balloons burst.

SUMMATION:

The lowering pressure in the bell jar simulates lowering ambient pressure as the diver ascends, holding his breath. The expanding balloons represent over-distended alveoli. As the pressure continues to lower, the balloons burst, dramatically splattering the inside of the bell jar with food coloring.

* Can usually be borrowed from a local school physics department.

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