Dive Master Exam

Question 1

Mediastinal Emphysema

Answer 1

results when air from lung rupture accumulates in the center of the chest over the heart

Question 2

Pneumothorax

Answer 2

results from expanding air forcing itself between the lung and the chest wall, collapsing the lung. Symptoms: chest pain, coughing blood, painful breathing

Question 3

Arterial Gas Embolism (AGE)

Answer 3

Gas bubbles going through arteries can make their way into the bloodstream and block blood flow

Question 4

Subcutaneous Emphysema

Answer 4

results when air from the rupture accumulates in the soft tissues at the base of the neck. Puts pressure on arteries going into the brain
Symptoms: sensation of fullness around the neck, Restricts blood flow so people get light headed

Question 5

Lung Over expansion Injuries

Answer 5

Apple Pie Makes Smiles

Arterial Gas embolism, Pneumothorax, Mediastinal emphysema, Subcutaneous emphysema

Question 6

CNS (Central Nervous System) Oxygen Toxicity

Answer 6

More life threatening, Becomes unacceptable when the PO2 reaches 1.6bar/ata but for rec divers is it 1.4bar/ata. Occurs when someone goes too deep and the partial pressure is too much. Seizures

Question 7

Pulmonary Oxygen Toxicity

Answer 7

When the diver is stays too close to the limits of diving. Such as repeated exposure to PO2s above .5bar/ata

Question 8

CNS Clock

Answer 8

used by Tec divers in calculating oxygen exposure in Pulmonary Oxygen Toxicity

Question 9

Ear and Sinus Barotrauma

Answer 9

Pressure injury, both squeezes and reverse blocks

Question 10

Middle Ear Squeeze / Eardrum Rupture

Answer 10

Failure to equalize on the descent, because middle ear hasn’t equalized, pressure forces blood and fluids into the middle ear. Ear feels full / Ear drum ruptures inward can cause vertigo and needs immediate EMS

Question 11

Round Window Rupture

Answer 11

Long forceful equalization. Inward pressure on the eardrum transfers through the ossicles to press on the oval window, vibrations cannot be transmitted to the cochlea

Question 12

Sinus Squeeze

Answer 12

most often from diving while congested

Question 13

Reverse block / Reverse Squeeze

Answer 13

Can happen in ear and sinuses, results when expanding air can’t exit the air space generally from congestion

Question 14

The Expanding Square

Answer 14

well suited to looking for something lost in the immediate area. Does not require special equipment.

Question 15

The U-Pattern

Answer 15

search a relatively large area for a medium to large object. Requires compass

Question 16

Circular Patterns

Answer 16

effective for smaller objects over unobstructed bottom. Requires 2 people

Question 17

M-Value

Answer 17

maximum tissue pressure allowed in a tissue. When surfacing prevent exceeding acceptable gradient. Lower M-Values when tissue dissolves the gas slowly.

Question 18

Haldanean Model

Answer 18

This model takes this into account and that’s how dives are planned. Tissues dissolve/absorb gases at different rates.

Question 19

Gas Narcosis

Answer 19

narcotic effect that gases can cause when breathed under elevated partial pressure PO2

Question 20

Decompression Illness (DCI)

Answer 20

Overall term that includes both DCS and lung over expansion injuries.

Question 21

Decompression Sickness (DCS)

Answer 21

when dissolved inert nitrogen (or other gases) comes out of the solution in tissues

Question 22

Hyperthermia

Answer 22

Too much heat. Symptoms: sweating and increase in pulse

Question 23

Heat Exhaustion

Answer 23

weak and rapid pulse, profuse perspiration, cool and clammy skin, nausea and weakness.
If not handled can turn into heat stroke

Question 24

Heat Stroke

Answer 24

Body’s cooling methods have failed resulting in no more sweating, hot/flushed skin and strong rapid pulse

Question 25

Hypothermia

Answer 25

too little heat in body

Question 26

Sound and Heat

Answer 26

Water absorbs heat approx. 20x faster than air does

Sound travels more than 4x faster in water than air

Question 27

Convection

Answer 27

Is a heat transmission assisted by the flow of a fluid. Warm water rises and cooler water descends. Contributes to body cooling while diving

Question 28

Conduction

Answer 28

Transmission of heat, two solids

Question 29

Draw out the Dive table

Answer 29

D = 0, 10, 20, 30, 40
P = 1, 2, 3, 4, 5
V = Full, 1/2, 1/3, 1/4, 1/5