Diving Theory & Safety Flashcards

A diver ascends too quickly from 30 meters. Which condition is MOST likely to result?

Answer: Decompression sickness

Rapid ascent allows dissolved nitrogen to form bubbles in tissues and blood, causing decompression sickness.

What is the purpose of the 'safety stop' recommended by PADI at 5 meters for 3 minutes?

Answer: To reduce the risk of decompression sickness

A safety stop at 5 meters for 3 minutes allows excess nitrogen to off-gas safely before surfacing.

Boyle's Law states that at a constant temperature, the volume of a gas is:

Answer: Inversely proportional to absolute pressure

Boyle's Law: as pressure increases, volume decreases proportionally (P₁V₁ = P₂V₂ at constant temperature).

Which gas law explains why a diver's lungs could rupture if they hold their breath during ascent?

Answer: Boyle's Law

Boyle's Law explains that trapped gas expands as pressure decreases during ascent, potentially rupturing the lungs.

What does a dive computer's 'no-decompression limit' (NDL) indicate?

Answer: The maximum time at depth before mandatory decompression stops are required

The NDL is the maximum time a diver can spend at a given depth without requiring decompression stops on ascent.

A diver experiences pain in their joints and muscles after a dive. This symptom is associated with which condition?

Answer: Decompression sickness (Type II)

Joint and muscle pain ('the bends') are classic Type II DCS symptoms caused by nitrogen bubble formation in tissues.

According to PADI standards, what is the maximum recommended ascent rate?

Answer: 9 meters per minute

PADI recommends ascending no faster than 9 meters (30 feet) per minute to allow safe nitrogen off-gassing.