Deep Diving Techniques & Planning Flashcards
7 cards from real PADI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Deep Diving Techniques & Planning flashcards as text
You are planning a deep dive to 100 feet in a location with a known thermocline at 60 feet. How should this affect your planning?
Answer: Plan for significantly reduced water temperature below 60 feet and pack appropriate exposure protection
Thermoclines mark sudden temperature drops, requiring divers to carry adequate thermal protection to prevent hypothermia at depth.
What is 'residual nitrogen' and how does it affect planning for a second dive?
Answer: Nitrogen remaining dissolved in body tissues after a dive; it reduces NDL on subsequent dives
Residual nitrogen is absorbed gas remaining in tissues after a dive, which shortens the no-decompression limit available during any subsequent dive.
Why should deep dives always be conducted as the FIRST dive of the day when planning multiple dives?
Answer: Residual nitrogen from earlier shallow dives reduces available NDL at depth, increasing DCS risk
Starting with the deepest dive ensures minimal residual nitrogen in tissues, maximizing available NDL and reducing decompression sickness risk.
A deep diver notices their air consumption rate is twice as fast as in shallow water at the same exertion level. What is the BEST explanation?
Answer: Increased pressure at depth compresses each breath, requiring more gas molecules per inhalation
At greater depths, ambient pressure compresses gas, so each breath delivers the same volume but contains more gas molecules, depleting the tank much faster.
When using a dive computer for a deep dive, what should a diver do if they accidentally exceed the planned maximum depth?
Answer: Monitor the computer's updated NDL and adjust bottom time accordingly, then ascend normally
Modern dive computers recalculate NDL continuously based on actual depth; divers should monitor the updated figures and ascend conservatively within the new limits.
What is the recommended action if a diver feels the effects of nitrogen narcosis severely impairing their judgment at depth?
Answer: Ascend to a shallower depth until symptoms improve, then reassess whether to continue
Ascending even a short distance significantly reduces narcosis effects because the partial pressure of nitrogen decreases with shallower depth.
Which pre-dive check is MOST critical specifically for deep dives compared to shallow recreational dives?
Answer: Verifying adequate gas supply and gas-sharing capability with buddy
At depth, gas consumption is much higher and out-of-air emergencies are more dangerous, making verification of sufficient gas and working octopus/alternate air source critical.