1
PADI Open Water Final Exam B Actual
Exam 2026/2027 – Complete Exam-Style
Questions with Detailed Rationales | 100%
Verified | Pass Guaranteed – A+ Graded
[SECTION 1: Diving Physics & Physiology — Questions 1-12]
Q1: According to Boyle's Law, if a diver takes a flexible container filled with air from the surface
(1 ATA) down to 66 feet (2 ATA), what happens to the volume of air inside the container?
A. The volume doubles.
B. The volume remains the same.
C. The volume is reduced by half.
D. The volume increases by one-third.
Correct Answer: C
Rationale: Boyle's Law states that for a fixed mass of gas at constant temperature, pressure and
volume are inversely proportional. Since pressure doubles from 1 ATA to 2 ATA, the volume of
the gas must be reduced by half. This principle explains why air spaces in the body (sinuses,
lungs, mask) shrink during descent.
Q2: A diver experiences pain and discomfort in their ears during descent. What is the primary
method to prevent this "squeeze"?
A. Descend feet first to increase pressure in the mask.
B. Equalize the air spaces in the ears and mask early and often during descent.
C. Exhale continuously to keep lung volume low.
D. Perform a Valsalva maneuver continuously on the bottom.
Correct Answer: B
,2
Rationale: Ear squeeze is caused by the failure to equalize the middle ear space to the increasing
ambient water pressure. Prevention involves gently blowing against a pinched nose (Valsalva) or
using the Toynbee maneuver to open the Eustachian tubes early and often during descent.
Descending feet first (A) helps mask squeeze but not ear squeeze.
Q3: Which condition is caused by a diver holding their breath while ascending, leading to over-
expansion of the lungs due to decreasing ambient pressure?
A. Arterial Gas Embolism (AGE)
B. Pulmonary Barotrauma
C. Decompression Sickness (DCS)
D. Nitrogen Narcosis
Correct Answer: B
Rationale: Pulmonary Barotrauma occurs when the expanding air in the lungs during ascent
cannot escape due to a closed glottis (holding breath), causing over-expansion and potential lung
tissue damage (pneumothorax). AGE (A) is caused by air bubbles entering the arterial
circulation, usually from lung over-expansion but distinct in mechanism.
Q4: What is the ambient pressure in atmospheres absolute (ATA) at a depth of 33 feet (10
meters) of seawater?
A. 1 ATA
B. 2 ATA
C. 3 ATA
D. 4 ATA
Correct Answer: B
Rationale: Ambient pressure increases by 1 ATA for every 33 feet (10 meters) of seawater. At 33
feet, the pressure is 2 atmospheres absolute (1 ATA of air pressure + 1 ATA of water pressure).
, 3
Q5: A diver begins to feel a sense of euphoria and impaired judgment at a depth of
approximately 100 feet (30 meters). What physiological condition is most likely occurring?
A. Oxygen Toxicity
B. Nitrogen Narcosis
C. Carbon Dioxide Retention
D. Hypothermia
Correct Answer: B
Rationale: Nitrogen Narcosis is the altered mental state caused by the narcotic effect of nitrogen
under pressure. It typically starts to become noticeable around 100 feet (30 meters) and deeper,
affecting judgment and reaction time. Oxygen toxicity (A) is usually a concern deeper or with
high PO2 mixtures.
Q6: What is the maximum operating depth limit for a PADI Open Water Diver using standard
air?
A. 40 feet (12 meters)
B. 60 feet (18 meters)
C. 100 feet (30 meters)
D. 130 feet (40 meters)
Correct Answer: B
Rationale: PADI Open Water Diver standards limit the maximum depth to 60 feet (18 meters) for
entry-level divers. Divers must be certified as Advanced Open Water Divers to reach depths up to
100 feet (30 meters). 40 feet (A) is the limit for Junior Open Water Divers (age 12-14).
Q7: Which of the following is a symptom of Central Nervous System (CNS) Oxygen Toxicity?
A. Tunnel vision and nausea
B. Joint pain ("the bends")
C. Itching and skin rash
PADI Open Water Final Exam B Actual
Exam 2026/2027 – Complete Exam-Style
Questions with Detailed Rationales | 100%
Verified | Pass Guaranteed – A+ Graded
[SECTION 1: Diving Physics & Physiology — Questions 1-12]
Q1: According to Boyle's Law, if a diver takes a flexible container filled with air from the surface
(1 ATA) down to 66 feet (2 ATA), what happens to the volume of air inside the container?
A. The volume doubles.
B. The volume remains the same.
C. The volume is reduced by half.
D. The volume increases by one-third.
Correct Answer: C
Rationale: Boyle's Law states that for a fixed mass of gas at constant temperature, pressure and
volume are inversely proportional. Since pressure doubles from 1 ATA to 2 ATA, the volume of
the gas must be reduced by half. This principle explains why air spaces in the body (sinuses,
lungs, mask) shrink during descent.
Q2: A diver experiences pain and discomfort in their ears during descent. What is the primary
method to prevent this "squeeze"?
A. Descend feet first to increase pressure in the mask.
B. Equalize the air spaces in the ears and mask early and often during descent.
C. Exhale continuously to keep lung volume low.
D. Perform a Valsalva maneuver continuously on the bottom.
Correct Answer: B
,2
Rationale: Ear squeeze is caused by the failure to equalize the middle ear space to the increasing
ambient water pressure. Prevention involves gently blowing against a pinched nose (Valsalva) or
using the Toynbee maneuver to open the Eustachian tubes early and often during descent.
Descending feet first (A) helps mask squeeze but not ear squeeze.
Q3: Which condition is caused by a diver holding their breath while ascending, leading to over-
expansion of the lungs due to decreasing ambient pressure?
A. Arterial Gas Embolism (AGE)
B. Pulmonary Barotrauma
C. Decompression Sickness (DCS)
D. Nitrogen Narcosis
Correct Answer: B
Rationale: Pulmonary Barotrauma occurs when the expanding air in the lungs during ascent
cannot escape due to a closed glottis (holding breath), causing over-expansion and potential lung
tissue damage (pneumothorax). AGE (A) is caused by air bubbles entering the arterial
circulation, usually from lung over-expansion but distinct in mechanism.
Q4: What is the ambient pressure in atmospheres absolute (ATA) at a depth of 33 feet (10
meters) of seawater?
A. 1 ATA
B. 2 ATA
C. 3 ATA
D. 4 ATA
Correct Answer: B
Rationale: Ambient pressure increases by 1 ATA for every 33 feet (10 meters) of seawater. At 33
feet, the pressure is 2 atmospheres absolute (1 ATA of air pressure + 1 ATA of water pressure).
, 3
Q5: A diver begins to feel a sense of euphoria and impaired judgment at a depth of
approximately 100 feet (30 meters). What physiological condition is most likely occurring?
A. Oxygen Toxicity
B. Nitrogen Narcosis
C. Carbon Dioxide Retention
D. Hypothermia
Correct Answer: B
Rationale: Nitrogen Narcosis is the altered mental state caused by the narcotic effect of nitrogen
under pressure. It typically starts to become noticeable around 100 feet (30 meters) and deeper,
affecting judgment and reaction time. Oxygen toxicity (A) is usually a concern deeper or with
high PO2 mixtures.
Q6: What is the maximum operating depth limit for a PADI Open Water Diver using standard
air?
A. 40 feet (12 meters)
B. 60 feet (18 meters)
C. 100 feet (30 meters)
D. 130 feet (40 meters)
Correct Answer: B
Rationale: PADI Open Water Diver standards limit the maximum depth to 60 feet (18 meters) for
entry-level divers. Divers must be certified as Advanced Open Water Divers to reach depths up to
100 feet (30 meters). 40 feet (A) is the limit for Junior Open Water Divers (age 12-14).
Q7: Which of the following is a symptom of Central Nervous System (CNS) Oxygen Toxicity?
A. Tunnel vision and nausea
B. Joint pain ("the bends")
C. Itching and skin rash
