PADI Recreational Dive Planner (RDP) 3 — Questions and Answers
Question 1: What is the maximum depth limit for recreational dives planned using the PADI RDP?
- 100 feet / 30 meters
- 130 feet / 40 meters (Correct answer)
- 120 feet / 36 meters
- 150 feet / 45 meters
Correct answer: 130 feet / 40 meters
The PADI RDP is designed for recreational dives to a maximum of 130 feet (40 meters).
Question 2: When planning a dive to 70 feet, which RDP depth column should you use if 70 feet is not listed?
- The next shallower depth column
- The next deeper depth column (Correct answer)
- Interpolate between 60 and 80 feet
- 70 feet is always listed on the RDP
Correct answer: The next deeper depth column
When your planned depth falls between listed depths, always use the next deeper depth column to plan conservatively.
Question 3: A diver plans a repetitive dive to 50 feet and finds an RNT of 47 minutes with an NDL of 100 minutes. What is the maximum Actual Bottom Time (ABT) for this dive?
- 100 minutes
- 53 minutes (Correct answer)
- 47 minutes
- 147 minutes
Correct answer: 53 minutes
Maximum ABT = NDL minus RNT, so 100 − 47 = 53 minutes.
Question 4: Which of the following best describes a 'no-decompression limit' (NDL) as shown in Table 1 of the RDP?
- The time you must wait on the surface between dives
- The maximum time at a given depth before mandatory decompression stops are required (Correct answer)
- The time needed to ascend safely from that depth
- The maximum depth you can reach on a single breath
Correct answer: The maximum time at a given depth before mandatory decompression stops are required
The NDL is the maximum bottom time at a given depth that keeps a diver within the no-decompression range.
Question 5: Why does the RDP use the deepest depth reached during a dive for planning purposes, even if most of the dive was shallower?
- Because deeper depths absorb more light, making navigation harder
- Because nitrogen absorption is greatest at the deepest point, and planning for worst-case protects the diver (Correct answer)
- Because shallow portions of a dive do not accumulate nitrogen
- Because the RDP cannot calculate multi-level profiles
Correct answer: Because nitrogen absorption is greatest at the deepest point, and planning for worst-case protects the diver
Nitrogen dissolves into tissues faster at greater pressure, so the RDP uses the deepest point as a conservative planning baseline.
Question 6: How does a safety stop differ from a required decompression stop in recreational diving?
- A safety stop is mandatory; a decompression stop is optional
- A safety stop is a precautionary 3-5 minute pause at 15 feet; a decompression stop is mandatory and required to avoid DCS (Correct answer)
- They are the same thing — both are required by the RDP
- A safety stop is only required after dives deeper than 100 feet
Correct answer: A safety stop is a precautionary 3-5 minute pause at 15 feet; a decompression stop is mandatory and required to avoid DCS
Safety stops are a precautionary best practice at 15 feet for 3–5 minutes, while decompression stops are mandatory and signal the diver exceeded no-decompression limits.
Question 7: On the RDP, what happens to the no-decompression limit as depth increases?
- It increases because deeper dives are safer
- It stays the same at all depths
- It decreases because nitrogen absorption is faster at greater depths (Correct answer)
- It doubles every 10 feet
Correct answer: It decreases because nitrogen absorption is faster at greater depths
Greater depth means higher pressure and faster nitrogen absorption, so the NDL gets shorter at greater depths.
PADI Recreational Dive Planner (RDP) 3
What is the maximum depth limit for recreational dives planned using the PADI RDP?