SDI Scuba Certification Exam Study
Guide (2025/2026) ACTUAL EXAM
COMPREHENSIVE QUESTIONS
AND VERIFIED ACCURATE
SOLUTION (DETAILED &
ELABORATED) |GET IT 100%
ACCURATE!! 2025 TEST!!
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
2) invented the personal dive
scuba diving
computer
changes that
3) equipment manufacturers made
occurred in
improvements to the design and
1950s
workmanship of gear
Name 3 different 1) dive tables
devices that 2) J-valves
modern dive 3) depth gauges
computers
replace
First dive training agency to provide
What sets SDI entry level scuba instruction that
apart from other incorporates the use of personal
training dive computers --> more
agencies? streamlined scuba course w/ more
instruction time in the water
How much Objects underwater appear 25%
larger and closer larger and 25% closer
do objects
appear As light travels through the airspace
underwater and created by the mask, it bends,
why? creating a magnifying effect.
, How much faster 4 times faster because water is
does sound about 800 times denser than air.
move through
water than air
and why?
What is the first Red (within first 25 feet)
color to be
absorbed
underwater?
When diving Slack tide
from shore, the
best time to dive
is when there is
the least amount
of tidal current.
_______ tide is
when there is no
horizontal water
movement.
Guide (2025/2026) ACTUAL EXAM
COMPREHENSIVE QUESTIONS
AND VERIFIED ACCURATE
SOLUTION (DETAILED &
ELABORATED) |GET IT 100%
ACCURATE!! 2025 TEST!!
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
2) invented the personal dive
scuba diving
computer
changes that
3) equipment manufacturers made
occurred in
improvements to the design and
1950s
workmanship of gear
Name 3 different 1) dive tables
devices that 2) J-valves
modern dive 3) depth gauges
computers
replace
First dive training agency to provide
What sets SDI entry level scuba instruction that
apart from other incorporates the use of personal
training dive computers --> more
agencies? streamlined scuba course w/ more
instruction time in the water
How much Objects underwater appear 25%
larger and closer larger and 25% closer
do objects
appear As light travels through the airspace
underwater and created by the mask, it bends,
why? creating a magnifying effect.
, How much faster 4 times faster because water is
does sound about 800 times denser than air.
move through
water than air
and why?
What is the first Red (within first 25 feet)
color to be
absorbed
underwater?
When diving Slack tide
from shore, the
best time to dive
is when there is
the least amount
of tidal current.
_______ tide is
when there is no
horizontal water
movement.
