PADI OPEN WATER DIVER CERTIFICATION
EXAM PREPARATION GUIDE QUESTIONS WITH
VERIFIED ANSWERS GRADED A+ 2026
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
1
,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#
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
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
2
, 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
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
3
EXAM PREPARATION GUIDE QUESTIONS WITH
VERIFIED ANSWERS GRADED A+ 2026
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
1
,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#
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
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
2
, 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
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
3
