PADI Recreational Dive Planner (RDP) 5 — Questions and Answers
Question 1: A diver plans three dives in one day. Which of the following is the MOST conservative planning approach?
- Start with the shallowest dive and end with the deepest
- Start with the deepest dive and gradually ascend to shallower depths on each subsequent dive (Correct answer)
- Alternate between deep and shallow dives to balance nitrogen
- Depth order does not affect nitrogen loading throughout the day
Correct answer: Start with the deepest dive and gradually ascend to shallower depths on each subsequent dive
Starting with the deepest dive and ending with the shallowest minimizes residual nitrogen accumulation and follows RDP best practices.
Question 2: If a diver wants to make three dives in one day using the RDP, how are the planning steps connected between dives?
- Each dive is planned independently from scratch
- The ending pressure group of each dive becomes the starting pressure group for the next surface interval calculation (Correct answer)
- Only the first and last dives need to be cross-referenced
- Three dives in one day require special computer software, not the RDP
Correct answer: The ending pressure group of each dive becomes the starting pressure group for the next surface interval calculation
The end pressure group of Dive 1 feeds into Table 2 for the surface interval, then Table 3 for Dive 2, and the same chain continues for Dive 3.
Question 3: When planning a dive at altitude using the PADI RDP, what adjustment must be made?
- No adjustment is needed — the RDP is valid at any altitude
- Use the altitude-adjusted RDP tables or special procedures because reduced atmospheric pressure changes nitrogen absorption rates (Correct answer)
- Always add 20 minutes to every no-decompression limit
- Reduce all depths by 10 feet when above 500 feet elevation
Correct answer: Use the altitude-adjusted RDP tables or special procedures because reduced atmospheric pressure changes nitrogen absorption rates
At altitude, the reduced atmospheric pressure means nitrogen behaves differently, requiring special altitude dive planning procedures.
Question 4: What does it mean if a diver's planned Total Bottom Time (TBT) exceeds the NDL for their repetitive dive depth?
- The diver may continue the dive but must ascend slower
- The planned dive is not permitted as a recreational dive — the diver must reduce either depth or time (Correct answer)
- A safety stop will make the dive acceptable
- The diver should surface, wait 5 minutes, and re-enter
Correct answer: The planned dive is not permitted as a recreational dive — the diver must reduce either depth or time
When TBT exceeds the NDL, the dive violates no-decompression limits and is not permitted in recreational diving — either depth or time must be reduced.
Question 5: Which symptom is MOST associated with decompression sickness (DCS), the risk the RDP is designed to minimize?
- Ear equalization pain during descent
- Joint pain, skin rash, numbness, or paralysis after surfacing (Correct answer)
- Mask squeeze causing red marks around the face
- Salt water aspiration causing coughing
Correct answer: Joint pain, skin rash, numbness, or paralysis after surfacing
DCS symptoms — joint pain, neurological symptoms, skin mottling — result from nitrogen bubbles forming in tissues when a diver ascends too quickly or exceeds NDLs.
Question 6: On the RDP, what does the shaded area on Table 1 indicate?
- Depths recommended for beginner divers only
- Dive times that would exceed the no-decompression limit and are not allowed (Correct answer)
- Times when a safety stop is optional
- The best depths for seeing marine life
Correct answer: Dive times that would exceed the no-decompression limit and are not allowed
Shaded cells on Table 1 represent depth-time combinations that exceed the no-decompression limit and therefore require decompression — not permitted in recreational diving.
Question 7: A student asks why the RDP tables are more conservative than actual decompression research. What is the BEST explanation?
- The tables were designed by non-divers who overestimated risk
- The RDP builds in safety margins because individual physiology, fitness, and conditions vary widely among recreational divers (Correct answer)
- The tables are updated every year and become less conservative over time
- The RDP is only meant for dives in cold water, so warm-water divers get extra margin
Correct answer: The RDP builds in safety margins because individual physiology, fitness, and conditions vary widely among recreational divers
The RDP includes conservative safety margins to account for individual variability, fatigue, cold, exertion, and other real-world factors that affect nitrogen absorption.
PADI Recreational Dive Planner (RDP) 5
A diver plans three dives in one day.
Which of the following is the MOST conservative planning approach?