SDI SCUBA CERTIFICATION EXAM STUDY GUIDE
EXPECTED QUESTIONS WITH VERIFIED ANSWERS
Question 1.
What should a diver do to alleviate the symptoms of nitrogen narcosis?
ANSWER
Ascend normally until you no longer feel the affects
Question 2.
List five factors that can predispose a diver to decompression sickness
ANSWER
1) age
2) repetitive dives
3) illness
4) obesity
5) drug and/or alcohol use prior to dive
Question 3.
What are 2 ways a PDC may alert a diver that they are ascending too fast?
ANSWER
1) alarm
2) blinking visual signal
Question 4.
What extra attire can enhance a diver's warmth when worn with a wet or dry suit?
ANSWER
hood
hooded vest
boots
gloves
cap
,Question 5.
State the gauges that a console might hold.
ANSWER
How much air is left in the tank (SPG) and depth gauge
Question 6.
How do you know if a mask fits properly?
ANSWER
try on without strap by placing over eyes and breathing in through nose - If tightens against
face and does not fall off, it is a proper fit
Question 7.
How much faster does sound move through water than air and why?
ANSWER
4 times faster because water is about 800 times denser than air.
Question 8.
What is the depth threshold where most scuba divers generally begin to be affected by nitrogen
narcosis?
ANSWER
30 meters sea water/100 feet sea water
Question 9.
what should you do if you suddenly feel sick and develop a headache during a scuba dive?
ANSWER
Abort dive with a controlled ascent
Breathe fresh air
Question 10.
Define no-stop time
ANSWER
The amount of time remaining at any point during a dive before incurring a mandatory
decompression stop.
, Question 11.
Name 2 basic fin designs and describe main features of each
ANSWER
1) Open Heel - heel strap, necessary when diving in cold water to enable the diver to wear
neoprene boots. Adjustable sizes are available.
2) Full Foot - encloses entire foot, must be appropriate fit, allows for more efficient use of leg
muscles.
Question 12.
Describe 2 different ways to indicate "OK."
ANSWER
at surface - both hands on top of head or tap head with fist of one hand underwater - pointer
finger pressed to thumb (making a circle) and other three fingers extended up
Question 13.
How much larger and closer do objects appear underwater and why?
ANSWER
Objects underwater appear 25% larger and 25% closer
As light travels through the airspace created by the mask, it bends, creating a magnifying
effect.
Question 14.
Define maximum dive depth
ANSWER
The deepest point reached during a dive
Question 15.
Define risk management.
ANSWER
a means of preventing problems and planning a response to any emergency that may arise.
Involves planning ahead, employing good diving practices, and knowing what to do before an
emergency arises.
EXPECTED QUESTIONS WITH VERIFIED ANSWERS
Question 1.
What should a diver do to alleviate the symptoms of nitrogen narcosis?
ANSWER
Ascend normally until you no longer feel the affects
Question 2.
List five factors that can predispose a diver to decompression sickness
ANSWER
1) age
2) repetitive dives
3) illness
4) obesity
5) drug and/or alcohol use prior to dive
Question 3.
What are 2 ways a PDC may alert a diver that they are ascending too fast?
ANSWER
1) alarm
2) blinking visual signal
Question 4.
What extra attire can enhance a diver's warmth when worn with a wet or dry suit?
ANSWER
hood
hooded vest
boots
gloves
cap
,Question 5.
State the gauges that a console might hold.
ANSWER
How much air is left in the tank (SPG) and depth gauge
Question 6.
How do you know if a mask fits properly?
ANSWER
try on without strap by placing over eyes and breathing in through nose - If tightens against
face and does not fall off, it is a proper fit
Question 7.
How much faster does sound move through water than air and why?
ANSWER
4 times faster because water is about 800 times denser than air.
Question 8.
What is the depth threshold where most scuba divers generally begin to be affected by nitrogen
narcosis?
ANSWER
30 meters sea water/100 feet sea water
Question 9.
what should you do if you suddenly feel sick and develop a headache during a scuba dive?
ANSWER
Abort dive with a controlled ascent
Breathe fresh air
Question 10.
Define no-stop time
ANSWER
The amount of time remaining at any point during a dive before incurring a mandatory
decompression stop.
, Question 11.
Name 2 basic fin designs and describe main features of each
ANSWER
1) Open Heel - heel strap, necessary when diving in cold water to enable the diver to wear
neoprene boots. Adjustable sizes are available.
2) Full Foot - encloses entire foot, must be appropriate fit, allows for more efficient use of leg
muscles.
Question 12.
Describe 2 different ways to indicate "OK."
ANSWER
at surface - both hands on top of head or tap head with fist of one hand underwater - pointer
finger pressed to thumb (making a circle) and other three fingers extended up
Question 13.
How much larger and closer do objects appear underwater and why?
ANSWER
Objects underwater appear 25% larger and 25% closer
As light travels through the airspace created by the mask, it bends, creating a magnifying
effect.
Question 14.
Define maximum dive depth
ANSWER
The deepest point reached during a dive
Question 15.
Define risk management.
ANSWER
a means of preventing problems and planning a response to any emergency that may arise.
Involves planning ahead, employing good diving practices, and knowing what to do before an
emergency arises.
