PADI Open Water Diver Certification Questions and Answers with Verified Solutions 2024 Graded A

SCUBA - Self contained underwater breathing apparatus

What is the pressure change for each 10m/33ft of depth change? - 1 bar/1 ata/1 atmosphere

What is the relationship between my depth in water and the pressure? - 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? - 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? - Volume will be 1/ata#
Density will be ata#

What 3 major body air spaces does increasing pressure affect as I descend? - Ears, sinuses, mask

What is a "squeeze"? - The discomfort caused by pressure imbalance pulling tissue into the air space

What is "equalization"? - The addition of air to your air spaces as you descend

How do I equalize as I descend? - 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? - Every meter/few feet, BEFORE you feel discomfort

What should I do if I can't equalize? - 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? - 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? - Congestion might block normal air flow, making equalization difficult or impossible

Why should I never dive with earplugs? - They create air spaces that you can't equalize

What other body air spaces are affected by increasing pressure? How do I equalize them? - 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? - Breathe continuously and never hold your breath

What can happen if I don't follow the most important rule in scuba diving? - Your lungs will over expand and rupture

What is a "reverse block"? - 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? - 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? - 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

What's the most efficient way to breathe dense air underwater? - Take slow, deep breaths

How do I breathe to reduce anxiety when under stress? - Do NOT breathe faster - keep breathing slowly

What are my 4 breathing rules as a scuba diver? - 1. Breathe continuously and never hold your breath
2. Breathe slowly and deeply
3. Don't allow yourself to get winded or out of breath
4. If faced with a problem, stop, and reduce anxiety by breathing slowly and deeply

What is buoyancy? - An upward force acting on an object in the water, canceling the pull of gravity

What causes buoyancy? - The upwards force is caused by the water displaced by the object, and is equal to the weight of displaced water

positive buoyancy - The object weighs less than the water it displaces, so it floats