NAUI Underwater Skills & Safety Procedures

Question 1

What is the primary reason for practicing controlled ascents during training?

Accepted Answer

To prevent decompression sickness and other injuries

Answer

Practicing controlled ascents during scuba diving training is crucial for safety, primarily to prevent decompression sickness (DCS) and lung over-expansion injuries. A slow, controlled ascent allows nitrogen absorbed by the body tissues to be safely released, preventing bubble formation that causes DCS. It also helps divers avoid rapid pressure changes that can damage lungs.

Question 2

Why is the buddy system important in scuba diving?

Accepted Answer

To provide immediate assistance during emergencies

Answer

The buddy system is fundamental in scuba diving because it ensures divers always have a partner to provide immediate assistance in case of an emergency. This includes sharing air, helping with equipment malfunctions, or assisting a diver who becomes disoriented or distressed. It significantly enhances safety by providing mutual support and accountability underwater.

Question 3

What does a slow ascent rate help prevent?

Accepted Answer

Decompression sickness

Answer

A slow ascent rate is vital in scuba diving to prevent decompression sickness (DCS), also known as "the bends." As a diver ascends, the ambient pressure decreases, causing nitrogen dissolved in the body's tissues to come out of solution. A slow ascent allows this nitrogen to be exhaled safely through the lungs, preventing the formation of bubbles that can cause DCS.

Question 4

What is the function of a safety stop during ascent?

Accepted Answer

To allow for nitrogen elimination

Answer

A safety stop is a crucial pause during ascent, typically at 15-20 feet for 3-5 minutes. Its primary function is to allow the body additional time to off-gas dissolved nitrogen from tissues. This controlled elimination of nitrogen significantly reduces the risk of decompression sickness (DCS) after a dive.

Question 5

Why is it important to equalize pressure in the ears during descent?

Accepted Answer

To prevent barotrauma

Answer

As a diver descends, increasing water pressure compresses the air in the middle ear. Equalizing pressure, by methods like Valsalva, introduces air into the middle ear to match the external pressure. Failing to equalize creates a painful pressure imbalance, which can lead to barotrauma, or tissue damage, to the eardrum or inner ear.

(NAUI) National Association of Underwater Instructors Certification Practice Test

(NAUI) National Association of Underwater Instructors Certification Practice Test

NAUI Underwater Skills & Safety Procedures