PADI Night & Limited Visibility Diving 5

Question 1

What is the best strategy for maintaining buddy contact in extremely limited visibility (less than 1 meter)?

Accepted Answer

Use a buddy line or tether between divers

Answer

A short buddy line (1–2 meters) physically connects the two divers, ensuring they cannot become separated even when visibility is zero.

Question 2

How does nitrogen narcosis risk compare between night and day dives at the same depth?

Accepted Answer

Nitrogen narcosis is depth-dependent only and is unaffected by ambient lighting

Answer

Nitrogen narcosis is driven purely by partial pressure of nitrogen at depth, not by light conditions, though darkness can compound the diver's perception of impairment.

Question 3

A night diver wants to photograph bioluminescent plankton. Which camera setting approach is most appropriate?

Accepted Answer

Shoot with strobes disabled, high ISO, and a slow shutter speed

Answer

Capturing bioluminescence requires a long exposure in total darkness — strobes would overpower the faint natural glow, and high ISO captures it without artificial light.

Question 4

Which surface condition should cause a dive team to CANCEL a planned night dive?

Accepted Answer

Dense fog reducing shore visibility to under 50 feet

Answer

Dense fog prevents surface support and boat traffic from seeing divers at the surface, creating a serious collision and rescue risk that outweighs the dive.

Question 5

What physiological change makes breathing work feel slightly harder during cold-water night dives, affecting air consumption?

Accepted Answer

Both increased regulator resistance and anxiety-related breathing changes

Answer

Cold air is denser, increasing regulator work of breathing, while the psychological stress of darkness often causes divers to breathe less efficiently — both raise air consumption.

(PADI) Certified Professional Association of Diving Instructors Diver Practice Test

(PADI) Certified Professional Association of Diving Instructors Diver Practice Test

PADI Night & Limited Visibility Diving 5