SDI SCUBA CERTIFICATION EXAM STUDY
GUIDE
1. Define SCUBA: S -
self C - contained
U-
underwater
B-
breathing A -
apparatus
2. List 3 important scuba diving changes that occurred in 1950s:
1) published USN dive tables
2) invented the personal dive computer
3) equipment manufacturers made improvements to the design and
workmanship of gear
3. Name 3 different devices that modern dive computers replace
1) dive tables
2) J-valves
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, SDI SCUBA CERTIFICATION EXAM STUDY
GUIDE
3) depth gauges
4. What sets SDI apart from other training agencies?: First dive
training agency to provide entry level scuba instruction that
incorporates the use of personal dive computers --> more streamlined
scuba course w/ more instruction time in the water
5. How much larger and closer do objects appear underwater
and why?: Ob- jects underwater appear 25% larger and 25% closer
As light travels through the airspace created by the mask, it bends,
creating a magnifying effect.
6. How much faster does sound move through water than air and
why?: 4 times faster because water is about 800 times denser than air.
7. What is the first color to be absorbed underwater?: Red (within
first 25 feet)
8. When diving from shore, the best time to dive is when
2/
, SDI SCUBA CERTIFICATION EXAM STUDY
GUIDE
there is the least amount of tidal current. tide is when there
is no horizontal water movement.: Slack tide
9. If you are caught in a rip current, first swim to the
current to get out of it before swimming towards shore.:
Parallel
10.Waves are usually caused by: Wind pushing water on the surface
11. T or F: Anticipate surge action to avoid contact with
stationary objects: -
True
12.What type of marine life cause most diving injuries?: Most
diving injuries result from animal's defensive response to a perceived
threat
13.What should you do if you see a potentially dangerous
animal underwater and it does not leave the area?: Remain still
and calm. Slowly leave area if necessary.
3/
GUIDE
1. Define SCUBA: S -
self C - contained
U-
underwater
B-
breathing A -
apparatus
2. List 3 important scuba diving changes that occurred in 1950s:
1) published USN dive tables
2) invented the personal dive computer
3) equipment manufacturers made improvements to the design and
workmanship of gear
3. Name 3 different devices that modern dive computers replace
1) dive tables
2) J-valves
1/
, SDI SCUBA CERTIFICATION EXAM STUDY
GUIDE
3) depth gauges
4. What sets SDI apart from other training agencies?: First dive
training agency to provide entry level scuba instruction that
incorporates the use of personal dive computers --> more streamlined
scuba course w/ more instruction time in the water
5. How much larger and closer do objects appear underwater
and why?: Ob- jects underwater appear 25% larger and 25% closer
As light travels through the airspace created by the mask, it bends,
creating a magnifying effect.
6. How much faster does sound move through water than air and
why?: 4 times faster because water is about 800 times denser than air.
7. What is the first color to be absorbed underwater?: Red (within
first 25 feet)
8. When diving from shore, the best time to dive is when
2/
, SDI SCUBA CERTIFICATION EXAM STUDY
GUIDE
there is the least amount of tidal current. tide is when there
is no horizontal water movement.: Slack tide
9. If you are caught in a rip current, first swim to the
current to get out of it before swimming towards shore.:
Parallel
10.Waves are usually caused by: Wind pushing water on the surface
11. T or F: Anticipate surge action to avoid contact with
stationary objects: -
True
12.What type of marine life cause most diving injuries?: Most
diving injuries result from animal's defensive response to a perceived
threat
13.What should you do if you see a potentially dangerous
animal underwater and it does not leave the area?: Remain still
and calm. Slowly leave area if necessary.
3/
