SSI Open Water Diving – Complete Study Guide, Key Concepts & Practice
Questions Review
Which of the statements concerning sound transmission underwater is correct? - ANS
✔✔Sound travels four times faster under water than in air
Divers find it difficult to locate the direction of a sound
Sound will travel farther underwater than in air
Proper equalization techniques must be learned in order to - ANS ✔✔Prevent ear pain
Prevent squeeze injuries
Prevent sinus squeeze
Underwater, the bending of light rays causes objects to appear to be - ANS ✔✔Closer
Earplugs - ANS ✔✔NEVER wear when diving
The condition in which certain colors are diminished as depth increases is called - ANS
✔✔Absorption
The absolute pressure expressed in terms of atmospheres absolute at 99 feet in salt water is -
ANS ✔✔4 ata
One atmosphere of pressure is defined as - ANS ✔✔Each 33 feet of depth is sea water
Each 34 feet in salt water
1 ata
Ear squeeze can be prevented by - ANS ✔✔Never diving with a cold
, Relaxing
Roatating the jaw, swallowing, Valsalva
The first symptom of a sinus squeeze is usually - ANS ✔✔A sharp pain or wedging sensation
above the eyes
Absolute Pressure - ANS ✔✔The total pressure exerted on an object
The purpose of equalization is to - ANS ✔✔Introduce additional air into body air spaces in
response to increasing external pressure
If a flexible air-filled container has a volume of 40 cu ft on the surface, what would the volume
be at 99 feet in sea water? (rounded off) - ANS ✔✔10 cu ft
The greatest relative pressure change in sea water takes place between ____ and ____ feet. -
ANS ✔✔0/33
Which of the statements concerning sound transmission underwater is correct - ANS
✔✔Difficult to locate direction
Sound travels 4x faster
Sound will travel farther
Body heat is lost underwater ___ than in air. - ANS ✔✔25-30 times faster
Salt water weighs ___ pounds per cubic foot and freshwater weighs ___ pounds per cubic foot. -
ANS ✔✔64/62.5
Gauge pressure - ANS ✔✔Absolute pressure minus 1 ata
Questions Review
Which of the statements concerning sound transmission underwater is correct? - ANS
✔✔Sound travels four times faster under water than in air
Divers find it difficult to locate the direction of a sound
Sound will travel farther underwater than in air
Proper equalization techniques must be learned in order to - ANS ✔✔Prevent ear pain
Prevent squeeze injuries
Prevent sinus squeeze
Underwater, the bending of light rays causes objects to appear to be - ANS ✔✔Closer
Earplugs - ANS ✔✔NEVER wear when diving
The condition in which certain colors are diminished as depth increases is called - ANS
✔✔Absorption
The absolute pressure expressed in terms of atmospheres absolute at 99 feet in salt water is -
ANS ✔✔4 ata
One atmosphere of pressure is defined as - ANS ✔✔Each 33 feet of depth is sea water
Each 34 feet in salt water
1 ata
Ear squeeze can be prevented by - ANS ✔✔Never diving with a cold
, Relaxing
Roatating the jaw, swallowing, Valsalva
The first symptom of a sinus squeeze is usually - ANS ✔✔A sharp pain or wedging sensation
above the eyes
Absolute Pressure - ANS ✔✔The total pressure exerted on an object
The purpose of equalization is to - ANS ✔✔Introduce additional air into body air spaces in
response to increasing external pressure
If a flexible air-filled container has a volume of 40 cu ft on the surface, what would the volume
be at 99 feet in sea water? (rounded off) - ANS ✔✔10 cu ft
The greatest relative pressure change in sea water takes place between ____ and ____ feet. -
ANS ✔✔0/33
Which of the statements concerning sound transmission underwater is correct - ANS
✔✔Difficult to locate direction
Sound travels 4x faster
Sound will travel farther
Body heat is lost underwater ___ than in air. - ANS ✔✔25-30 times faster
Salt water weighs ___ pounds per cubic foot and freshwater weighs ___ pounds per cubic foot. -
ANS ✔✔64/62.5
Gauge pressure - ANS ✔✔Absolute pressure minus 1 ata
