Scuba Diving Open Water 5 — Questions and Answers
Question 1: What does 'positive buoyancy' mean for a diver at the surface?
- The diver sinks slowly when still
- The diver floats without effort (Correct answer)
- The diver is neutrally suspended mid-water
- The diver requires extra weight to descend
Correct answer: The diver floats without effort
Positive buoyancy means the diver's overall density is less than water, causing them to float — the desired state at the surface for safety.
Question 2: Which environmental hazard should a diver be most cautious about when diving near a coral reef?
- Rapidly changing salinity levels
- Accidentally touching or kicking fragile coral (Correct answer)
- Excessive freshwater runoff
- Magnetic interference from rock formations
Correct answer: Accidentally touching or kicking fragile coral
Coral is extremely fragile and slow-growing; physical contact from fins, hands, or equipment can damage colonies that took decades to form.
Question 3: What is the recommended minimum surface interval between two recreational dives to reduce DCS risk?
- 15 minutes
- 30 minutes (Correct answer)
- 1 hour
- 2 hours
Correct answer: 30 minutes
Most recreational dive tables and computers recommend a minimum surface interval of at least one hour between dives, though the specific time varies based on depth and bottom time.
Question 4: What does 'skip breathing' mean and why is it dangerous?
- Breathing only from the nose; wastes air
- Holding the breath to conserve air; risks lung overexpansion injury (Correct answer)
- Alternating between regulator and snorkel; causes CO2 build-up
- Breathing too fast; causes hyperventilation
Correct answer: Holding the breath to conserve air; risks lung overexpansion injury
Skip breathing (intentionally holding the breath to save air) violates the cardinal rule of scuba and risks pulmonary barotrauma from expanding gases during ascent.
Question 5: What type of dive site condition most increases the risk of a diver being swept away?
- Surge from wave action in calm conditions
- Strong tidal or rip currents (Correct answer)
- Low visibility due to silt
- Thermoclines with temperature variation
Correct answer: Strong tidal or rip currents
Strong tidal or rip currents can overpower even experienced swimmers, sweeping divers away from the dive site or their boat rapidly.
Question 6: If a fellow diver is unconscious at the surface, what is the first priority?
- Check their air supply and pressure gauge
- Establish positive buoyancy and secure their airway (Correct answer)
- Remove their BCD and tank to lighten the load
- Signal for help before approaching them
Correct answer: Establish positive buoyancy and secure their airway
Keeping an unconscious diver afloat with an open airway is the immediate priority, as drowning can occur within minutes if they sink face-down.
Question 7: What is the key difference between a 'dry suit' and a 'wet suit' in terms of thermal protection?
- Dry suits use thicker neoprene to trap more water
- Dry suits keep the diver's body dry by sealing out water completely (Correct answer)
- Wet suits are warmer because they hold air instead of water
- Dry suits are only used in tropical environments
Correct answer: Dry suits keep the diver's body dry by sealing out water completely
A dry suit uses waterproof seals at the wrists and neck to keep the diver completely dry, trapping an insulating air or undergarment layer for superior warmth in cold water.
Scuba Diving Open Water 5
What does 'positive buoyancy' mean for a diver at the surface?