SDI SCUBA CERTIFICATION
EXAM STUDY GUIDE WITH 100%
COMPLETE SOLUTIONS
Define SCUBA - CORRECT-ANSWER-S - self
C - contained
U - underwater
B - breathing
A - apparatus
Name 3 different devices that modern dive computers replace -
CORRECT-ANSWER-1) dive tables
2) J-valves
3) depth gauges
,List 3 important scuba diving changes that occurred in 1950s -
CORRECT-ANSWER-1) published USN dive tables
2) invented the personal dive computer
3) equipment manufacturers made improvements to the design and
workmanship of gear
What is the absolute pressure (in atm/bar) at 20 meters (66 feet)? -
CORRECT-ANSWER-3 atm/bar
What will be the volume in a ball that is filled with 2 cubic feet/liters of
air at 30 meters (90 feet) when it is taken to surface? - CORRECT-
ANSWER-8 cubic feet/liter (4x the volume)
How many more times dense is the air in a ballon at 4 atm/bar
compared to air density at surface? - CORRECT-ANSWER-4x
If a scuba cylinder lasts two hours at sea level, how long will it last at 20
m/66 ft? - CORRECT-ANSWER-40 minutes
, 120 min x 1/3 (vol) = 40 min
How often should a scuba diver equalize during descent? - CORRECT-
ANSWER-At the surface before descent and every couple of feet
What should you do if you experience discomfort in your ears upon
descending? - CORRECT-ANSWER-Stop, ascend a few feet until you no
longer feel discomfort, equalize again, then continue with descent
What is a reverse block? - CORRECT-ANSWER-When air cannot escape
freely from an air space during ascent
causes pain and discomfort in the ears and sinuses
What should you do if you experience a reverse block upon ascending?
- CORRECT-ANSWER-Stop, descend a few feet until pain subsides, wait
to allow air to vent, then continue with ascent
EXAM STUDY GUIDE WITH 100%
COMPLETE SOLUTIONS
Define SCUBA - CORRECT-ANSWER-S - self
C - contained
U - underwater
B - breathing
A - apparatus
Name 3 different devices that modern dive computers replace -
CORRECT-ANSWER-1) dive tables
2) J-valves
3) depth gauges
,List 3 important scuba diving changes that occurred in 1950s -
CORRECT-ANSWER-1) published USN dive tables
2) invented the personal dive computer
3) equipment manufacturers made improvements to the design and
workmanship of gear
What is the absolute pressure (in atm/bar) at 20 meters (66 feet)? -
CORRECT-ANSWER-3 atm/bar
What will be the volume in a ball that is filled with 2 cubic feet/liters of
air at 30 meters (90 feet) when it is taken to surface? - CORRECT-
ANSWER-8 cubic feet/liter (4x the volume)
How many more times dense is the air in a ballon at 4 atm/bar
compared to air density at surface? - CORRECT-ANSWER-4x
If a scuba cylinder lasts two hours at sea level, how long will it last at 20
m/66 ft? - CORRECT-ANSWER-40 minutes
, 120 min x 1/3 (vol) = 40 min
How often should a scuba diver equalize during descent? - CORRECT-
ANSWER-At the surface before descent and every couple of feet
What should you do if you experience discomfort in your ears upon
descending? - CORRECT-ANSWER-Stop, ascend a few feet until you no
longer feel discomfort, equalize again, then continue with descent
What is a reverse block? - CORRECT-ANSWER-When air cannot escape
freely from an air space during ascent
causes pain and discomfort in the ears and sinuses
What should you do if you experience a reverse block upon ascending?
- CORRECT-ANSWER-Stop, descend a few feet until pain subsides, wait
to allow air to vent, then continue with ascent
