Scuba Diving Dive Planning and Tables 2

Question 1

What is the minimum surface interval recommended between dives when using the PADI RDP?

Accepted Answer

It depends on the pressure group — tables provide specific minimum intervals

Answer

The RDP table provides the minimum surface interval required based on the diver's pressure group after the first dive and the planned depth of the next dive.

Question 2

What is 'total bottom time' (TBT) in repetitive dive planning?

Accepted Answer

Residual nitrogen time plus actual bottom time of the current dive

Answer

Total bottom time equals the residual nitrogen time (from prior dives) added to the actual bottom time of the current dive, used to find the ending pressure group.

Question 3

What effect does diving at altitude have on standard sea-level dive tables?

Accepted Answer

Tables must be adjusted because ambient pressure is lower at altitude

Answer

At altitude, lower ambient pressure means sea-level tables underestimate decompression risk, so altitude-specific tables or adjustments are required.

Question 4

What is 'decompression sickness' (DCS) caused by?

Accepted Answer

Nitrogen bubbles forming in tissues and blood when pressure is reduced too quickly

Answer

DCS occurs when dissolved nitrogen comes out of solution and forms bubbles in tissues and the bloodstream due to an ascent that is too rapid or exceeding NDLs.

Question 5

Why should flying after diving be delayed?

Accepted Answer

Cabin altitude reduces pressure, increasing DCS risk from residual nitrogen

Answer

Aircraft cabins are pressurized to the equivalent of 6,000–8,000 feet, which is lower than sea-level pressure, promoting nitrogen bubble formation from residual tissue nitrogen.

Scuba Diving Practice Test

Scuba Diving Practice Test

Scuba Diving Dive Planning and Tables 2