1|Page
2025 Latest SSI Open Water Diver Certification
Exam – 150 Practice Questions and Correct
Answers / SSI Open Water Diver Practice Test
SCUBA - ...ANSWER...✓✓ Self contained underwater
breathing apparatus
What is the pressure change for each 10m/33ft of depth
change? - ...ANSWER...✓✓ 1 bar/1 ata/1 atmosphere
What is the relationship between my depth in water and
the pressure? - ...ANSWER...✓✓ The deeper you go in
water, the more the pressure increases
Pressure is expressed as the weight of air
What is the relationship between pressure, and the
volume and the density of air? - ...ANSWER...✓✓ As
pressure increases, the gas volume decreases and the
gas density increases
If I take a volume of air from one depth to another depth,
how much will the volume and density change? -
...ANSWER...✓✓ Volume will be 1/ata#
,2|Page
Density will be ata#
What 3 major body air spaces does increasing pressure
affect as I descend? - ...ANSWER...✓✓ Ears, sinuses,
mask
What is a "squeeze"? - ...ANSWER...✓✓ The discomfort
caused by pressure imbalance pulling tissue into the air
space
What is "equalization"? - ...ANSWER...✓✓ The addition of
air to your air spaces as you descend
How do I equalize as I descend? - ...ANSWER...✓✓ For
ears and sinuses, pinch your nose and blow gently, or
wiggle your jaw and swallow
For mask, blow into it with nose
How often should I equalize? - ...ANSWER...✓✓ Every
meter/few feet, BEFORE you feel discomfort
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What should I do if I can't equalize? - ...ANSWER...✓✓
Stop your descent, signal problem and point to your ear,
ascend a bit, and try again
What can happen if I don't or can't equalize gently and
keep descending? - ...ANSWER...✓✓ Fluid can rupture the
eardrum
Bruising around the face can occur
Why does a congestion from a cold or allergy temporarily
keep me from diving? - ...ANSWER...✓✓ Congestion might
block normal air flow, making equalization difficult or
impossible
Why should I never dive with earplugs? - ...ANSWER...✓✓
They create air spaces that you can't equalize
What other body air spaces are affected by increasing
pressure? How do I equalize them? - ...ANSWER...✓✓ In
filled teeth - go to a dentist
In a dry suit - learn from an instructor
Lungs - breathe normally and continuously
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What is the most important rule in scuba diving? -
...ANSWER...✓✓ Breathe continuously and never hold
your breath
What can happen if I don't follow the most important rule
in scuba diving? - ...ANSWER...✓✓ Your lungs will over
expand and rupture
What is a "reverse block"? - ...ANSWER...✓✓ When
expanding air becomes trapped in your body air spaces
as you ascend
What should I do if I feel discomfort in my ears, sinuses,
stomach, intestines, or teeth while ascending? -
...ANSWER...✓✓ Stop your ascent and descend a
meter/few feet to reduce discomfort and give trapped air
time to work its way out
How does depth affect how long my air supply lasts? -
...ANSWER...✓✓ The deeper you are, the more dense air
you breathe, and the faster you use the air in your
cylinder. Compared to the surface, air supply lasts 1/#ata
as long along with other factors
2025 Latest SSI Open Water Diver Certification
Exam – 150 Practice Questions and Correct
Answers / SSI Open Water Diver Practice Test
SCUBA - ...ANSWER...✓✓ Self contained underwater
breathing apparatus
What is the pressure change for each 10m/33ft of depth
change? - ...ANSWER...✓✓ 1 bar/1 ata/1 atmosphere
What is the relationship between my depth in water and
the pressure? - ...ANSWER...✓✓ The deeper you go in
water, the more the pressure increases
Pressure is expressed as the weight of air
What is the relationship between pressure, and the
volume and the density of air? - ...ANSWER...✓✓ As
pressure increases, the gas volume decreases and the
gas density increases
If I take a volume of air from one depth to another depth,
how much will the volume and density change? -
...ANSWER...✓✓ Volume will be 1/ata#
,2|Page
Density will be ata#
What 3 major body air spaces does increasing pressure
affect as I descend? - ...ANSWER...✓✓ Ears, sinuses,
mask
What is a "squeeze"? - ...ANSWER...✓✓ The discomfort
caused by pressure imbalance pulling tissue into the air
space
What is "equalization"? - ...ANSWER...✓✓ The addition of
air to your air spaces as you descend
How do I equalize as I descend? - ...ANSWER...✓✓ For
ears and sinuses, pinch your nose and blow gently, or
wiggle your jaw and swallow
For mask, blow into it with nose
How often should I equalize? - ...ANSWER...✓✓ Every
meter/few feet, BEFORE you feel discomfort
,3|Page
What should I do if I can't equalize? - ...ANSWER...✓✓
Stop your descent, signal problem and point to your ear,
ascend a bit, and try again
What can happen if I don't or can't equalize gently and
keep descending? - ...ANSWER...✓✓ Fluid can rupture the
eardrum
Bruising around the face can occur
Why does a congestion from a cold or allergy temporarily
keep me from diving? - ...ANSWER...✓✓ Congestion might
block normal air flow, making equalization difficult or
impossible
Why should I never dive with earplugs? - ...ANSWER...✓✓
They create air spaces that you can't equalize
What other body air spaces are affected by increasing
pressure? How do I equalize them? - ...ANSWER...✓✓ In
filled teeth - go to a dentist
In a dry suit - learn from an instructor
Lungs - breathe normally and continuously
, 4|Page
What is the most important rule in scuba diving? -
...ANSWER...✓✓ Breathe continuously and never hold
your breath
What can happen if I don't follow the most important rule
in scuba diving? - ...ANSWER...✓✓ Your lungs will over
expand and rupture
What is a "reverse block"? - ...ANSWER...✓✓ When
expanding air becomes trapped in your body air spaces
as you ascend
What should I do if I feel discomfort in my ears, sinuses,
stomach, intestines, or teeth while ascending? -
...ANSWER...✓✓ Stop your ascent and descend a
meter/few feet to reduce discomfort and give trapped air
time to work its way out
How does depth affect how long my air supply lasts? -
...ANSWER...✓✓ The deeper you are, the more dense air
you breathe, and the faster you use the air in your
cylinder. Compared to the surface, air supply lasts 1/#ata
as long along with other factors
