PADI Divemaster Certification Practice Exam

When planning repetitive dives, what guideline should generally be followed?

1. Dive deeper with each subsequent dive

2. Dive shallower with each subsequent dive

3. Complete all dives with a maximum time limit of 20 minutes

4. Only perform one dive in a day

The correct answer is: Dive shallower with each subsequent dive

When planning repetitive dives, it is advisable to dive shallower with each subsequent dive to mitigate the risk of decompression sickness. This guideline stems from the principles of dive physics and physiology, which state that the accumulation of nitrogen in the body increases with deeper dives and longer exposure times. As divers ascend shallower after a deeper dive, the amount of nitrogen absorbed in the body is reduced more effectively during shallower dives. By diving shallower subsequently, divers allow their bodies time to off-gas accumulated nitrogen safely while still enjoying the underwater environment. This approach is in line with the use of dive tables or dive computers, which help manage no-decompression limits and track nitrogen saturation. The other options suggest practices that could increase the risk of decompression sickness. Diving deeper with each successive dive does not allow the body adequate time to off-gas nitrogen and can lead to increased absorption of nitrogen. Setting a maximum dive time of 20 minutes does not take into consideration the depth of the dive, which is crucial for safe diving practices. Finally, limiting oneself to just one dive a day does not utilize the possibilities for safe multiple dives provided the appropriate guidelines are followed. Therefore, diving shallower each time is a foundational practice for safe repetitive diving.