PADI Cheat Sheet 2026

The 30 highest-yield PADI facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which of the following best describes a key competency required for instructor development & teaching in PADI practice? → Strong analytical skills combined with effective communication and ethical judgment
2. Which component in a BCD oral inflator allows the diver to add air by mouth without it escaping back out? → A one-way check valve inside the mouthpiece assembly
3. A diver notices their SPG reads lower than expected at the start of a dive. What is the most likely explanation? → The cylinder was not fully filled or gas was lost from a leaking valve
4. What is the primary advantage of shooting in RAW format for underwater photography? → Post-processing allows extensive white balance and color correction
5. What natural phenomenon can a diver use to estimate north-south orientation on a sunny day in shallow water? → Sun position — the sun rises in the east and sets in the west, casting predictable shadows
6. Which diving practice causes the most physical damage to coral reefs during recreational diving? → Poor buoyancy control leading to contact with corals
7. In cave diving, what is a 'jump' or 'jump connection'? → A technique to cross from one guideline to another at a T or junction
8. What does the term 'depth of field' mean in underwater photography? → The range of distances in a scene that appear acceptably sharp
9. Thermoclines encountered during a night dive can reduce visibility dramatically. What is the primary reason? → The boundary between water layers of different temperatures refracts and scatters light
10. During an open water dive, a student signals that they are out of air at 12 meters. Which response demonstrates correct instructor action? → Share air via the alternate air source and ascend together
11. A diver notices bioluminescent organisms glowing in the water during a night dive. What should the diver do to best observe this phenomenon? → Turn off lights and wave a hand gently through the water
12. Which factor MOST increases the risk of a diver requiring rescue during a dive? → Diving beyond their training and experience level
13. Which gas law explains why a full scuba tank will show a lower pressure reading on a cold day compared to a warm day? → Charles's Law
14. When a diver plans a navigation dive with a heading of 045° (northeast), what is the return heading? → 225°
15. What is the purpose of the 'safety stop' recommended by PADI at 5 meters for 3 minutes? → To reduce the risk of decompression sickness
16. Which marine organism is the primary producer at the base of most open-ocean food webs? → Phytoplankton
17. A macro photographer wants to capture a tiny nudibranch on a black sand slope. What background technique creates the most dramatic images? → Use a wide aperture and shoot slightly upward to use the blue water as background
18. What is the recommended minimum number of lights a cave diver should carry? → One primary and two backups
19. What is the first step in assisting a distressed diver? → Approach calmly and assess
20. A Divemaster notices their group's dive profile would require a decompression stop. What should they do? → Adjust the dive plan to remain within no-decompression limits before descending
21. A diver surfaces complaining of severe fatigue, skin rashes, and joint pain 12 hours after a repetitive dive day. What is the most likely diagnosis? → Decompression sickness (DCS)
22. In the context of PADI certification, what is the most important consideration when implementing night & limited visibility diving? → Ensuring alignment with established standards, stakeholder needs, and best practices
23. What is the primary limitation of a magnetic compass when diving near certain underwater structures? → Metal objects and iron-rich rock can cause magnetic deviation
24. A diver experiences pain in their joints and muscles after a dive. This symptom is associated with which condition? → Decompression sickness (Type II)
25. What is the purpose of underwater navigation skills? → Navigate safely underwater
26. A diver swims a U-shaped navigation pattern. After completing the U, where should the diver end up relative to the starting point? → Parallel to and offset from the start, not back at the exact starting point
27. A regulator second stage that constantly frees flows underwater most likely has which problem? → A damaged or improperly seated demand valve or exhaust valve
28. Which process describes how nutrients cycle from dead organic matter back into the marine food web? → Decomposition by bacteria and fungi
29. What is the role of a pressure gauge? → Monitor air pressure
30. What is the PADI teaching model sequence used for skill instruction? → Tell → Show → Do → Review