10/14/25, 2:36 PM SDI Scuba Certification Exam Study Guide Exam (2025) Exam Questions & Answers | Latest Already Graded A+ UPDATE 2025|2…
SDI Scuba Certification Exam Study Guide Exam
(2025) Exam Questions & Answers | Latest
Already Graded A+ UPDATE 2025|2026!!
Save
Terms in this set (81)
S - self
C - contained
Define SCUBA U - underwater
B - breathing
A - apparatus
1) published USN dive tables
List 3 important scuba
2) invented the personal dive computer
diving changes that
3) equipment manufacturers made improvements to
occurred in 1950s
the design and workmanship of gear
Name 3 different devices 1) dive tables
that modern dive 2) J-valves
computers replace 3) depth gauges
First dive training agency to provide entry level scuba
What sets SDI apart from instruction that incorporates the use of personal dive
other training agencies? computers --> more streamlined scuba course w/
more instruction time in the water
Objects underwater appear 25% larger and 25%
How much larger and closer
closer do objects appear
underwater and why? As light travels through the airspace created by the
mask, it bends, creating a magnifying effect.
https://quizlet.com/1092485973/sdi-scuba-certification-exam-study-guide-exam-2025-exam-questions-answers-latest-already-graded-a-update-20252… 1/14
, 10/14/25, 2:36 PM SDI Scuba Certification Exam Study Guide Exam (2025) Exam Questions & Answers | Latest Already Graded A+ UPDATE 2025|2…
How much faster does 4 times faster because water is about 800 times
sound move through denser than air.
water than air and why?
What is the first color to Red (within first 25 feet)
be absorbed underwater?
When diving from shore, Slack tide
the best time to dive is
when there is the least
amount of tidal current.
_______ tide is when there is
no horizontal water
movement.
If you are caught in a rip Parallel
current, first swim _____ to
the current to get out of it
before swimming towards
shore.
Waves are usually caused Wind pushing water on the surface
by
T or F: Anticipate surge True
action to avoid contact
with stationary objects
What type of marine life Most diving injuries result from animal's defensive
cause most diving response to a perceived threat
injuries?
What should you do if you Remain still and calm. Slowly leave area if necessary.
see a potentially
dangerous animal
underwater and it does
not leave the area?
https://quizlet.com/1092485973/sdi-scuba-certification-exam-study-guide-exam-2025-exam-questions-answers-latest-already-graded-a-update-20252… 2/14
SDI Scuba Certification Exam Study Guide Exam
(2025) Exam Questions & Answers | Latest
Already Graded A+ UPDATE 2025|2026!!
Save
Terms in this set (81)
S - self
C - contained
Define SCUBA U - underwater
B - breathing
A - apparatus
1) published USN dive tables
List 3 important scuba
2) invented the personal dive computer
diving changes that
3) equipment manufacturers made improvements to
occurred in 1950s
the design and workmanship of gear
Name 3 different devices 1) dive tables
that modern dive 2) J-valves
computers replace 3) depth gauges
First dive training agency to provide entry level scuba
What sets SDI apart from instruction that incorporates the use of personal dive
other training agencies? computers --> more streamlined scuba course w/
more instruction time in the water
Objects underwater appear 25% larger and 25%
How much larger and closer
closer do objects appear
underwater and why? As light travels through the airspace created by the
mask, it bends, creating a magnifying effect.
https://quizlet.com/1092485973/sdi-scuba-certification-exam-study-guide-exam-2025-exam-questions-answers-latest-already-graded-a-update-20252… 1/14
, 10/14/25, 2:36 PM SDI Scuba Certification Exam Study Guide Exam (2025) Exam Questions & Answers | Latest Already Graded A+ UPDATE 2025|2…
How much faster does 4 times faster because water is about 800 times
sound move through denser than air.
water than air and why?
What is the first color to Red (within first 25 feet)
be absorbed underwater?
When diving from shore, Slack tide
the best time to dive is
when there is the least
amount of tidal current.
_______ tide is when there is
no horizontal water
movement.
If you are caught in a rip Parallel
current, first swim _____ to
the current to get out of it
before swimming towards
shore.
Waves are usually caused Wind pushing water on the surface
by
T or F: Anticipate surge True
action to avoid contact
with stationary objects
What type of marine life Most diving injuries result from animal's defensive
cause most diving response to a perceived threat
injuries?
What should you do if you Remain still and calm. Slowly leave area if necessary.
see a potentially
dangerous animal
underwater and it does
not leave the area?
https://quizlet.com/1092485973/sdi-scuba-certification-exam-study-guide-exam-2025-exam-questions-answers-latest-already-graded-a-update-20252… 2/14
