Approximately how much denser is the air a diver breathes at a depth of 30 meters/99 feet as compared to the surface?

Sound travels _____ times faster in water than in air because water is so much _______ than air.

What part of the ear is most affected by changes in pressure?

Which of the following are symptoms of nitrogen narcosis?

Above what altitude must you use special procedures for using the Recreational Dive Planner to plan your dives?

The Recreational Dive Planner used how many tissue compartments in the model and what was the half-time used for calculating surface interval credit?

What environmental element is primarily responsible for causing waves?

What happens if a diver is overweighted?

Where should you place an alternate air source?

Which connection on a scuba tank allows the regulator to be screwed directly into the tank valve?

What is the primary purpose of the circulatory and respiratory systems?

The best first aid treatment is emergency oxygen, preferably 100% for:

When immersed in cold water, the body responds with:

What is a squeeze caused by?

Why is oxygen the recommended first aid for DCI?

If you rupture your eardrum while diving:

What are the signs and symptoms of extremely advanced hypothermia?

Carotid sinus reflex can cause unconsciousness and may be caused by:

Which part of the ear is most affected by change in pressure?

What can happen if a diver equalizes too forcefully against a pinched nose?

What is the medical term for a pressure related injury?

Factors that might contribute to a diver getting DCI include:

What is the key part of red blood cells that aids in the transport of oxygen?

If a diver surfaces and soon after complains of difficulty breathing, paralysis or becomes unconscious, you should suspect:

Why is carbon monoxide poisoning so important to divers?

Why shouldn’t you fill scuba tanks with pure oxygen (for recreational use)?

Type II DCS signs & symptoms include:

To avoid shallow water blackout:

What is a dead air space?

Where does gas exchange occur in the body? [mark all that are correct]