NAUI Equipment Use & Maintenance 2 — Questions and Answers
Question 1: After a saltwater dive, what is the most important first step when rinsing your regulator?
- Blow air through the second stage before submerging in fresh water (Correct answer)
- Submerge the first stage with the dust cap removed to flush salt
- Disassemble the second stage completely before rinsing
- Soak the entire regulator in warm soapy water for 30 minutes
Correct answer: Blow air through the second stage before submerging in fresh water
Purging air through the second stage before rinsing prevents water from entering the first stage through the low-pressure port.
Question 2: Which BCD component is most likely to trap salt crystals and cause corrosion if not properly rinsed?
- The shoulder straps
- The inflator/deflator mechanism (Correct answer)
- The outer nylon shell
- The cummerbund buckle
Correct answer: The inflator/deflator mechanism
The inflator/deflator mechanism has small internal valves and passageways where salt crystals accumulate and cause sticking or corrosion.
Question 3: When storing a wetsuit long-term, which method best preserves the neoprene?
- Fold it tightly to minimize storage space
- Hang it on a wide hanger in a cool, dark area (Correct answer)
- Store it compressed in a mesh bag
- Roll it tightly with the lining facing outward
Correct answer: Hang it on a wide hanger in a cool, dark area
Hanging a wetsuit on a wide hanger in a cool, dark location prevents creasing, UV degradation, and compression of neoprene cells.
Question 4: A diver notices their submersible pressure gauge (SPG) reads higher than expected at the surface before a dive. What is the most likely cause?
- The cylinder is over-pressurized beyond its rated fill pressure
- The gauge is faulty and needs servicing
- Ambient temperature increase has raised cylinder pressure (Correct answer)
- The burst disk has failed and is restricting gas flow
Correct answer: Ambient temperature increase has raised cylinder pressure
Gas pressure increases with temperature; a cylinder filled in a cool environment will read higher when warmed by sun or ambient heat.
Question 5: What does a milky or cloudy appearance inside a diving mask lens typically indicate?
- Normal fogging that clears once the mask is rinsed
- Delamination of a tempered glass coating
- Salt residue from inadequate post-dive rinsing (Correct answer)
- UV damage from prolonged sun exposure
Correct answer: Salt residue from inadequate post-dive rinsing
A cloudy mask interior usually results from salt crystal buildup caused by insufficient fresh-water rinsing after dives.
Question 6: Which tool is specifically recommended for inspecting the interior of a scuba cylinder?
- A borescope or cylinder inspection light (Correct answer)
- A standard LED flashlight angled through the valve port
- An endoscope designed for medical use
- Visual inspection is not possible; only hydrostatic testing is required
Correct answer: A borescope or cylinder inspection light
A borescope or dedicated cylinder inspection light is designed to illuminate and magnify the interior walls for visual inspection.
Question 7: A diver's fin strap breaks mid-dive trip. Which field repair is most practical and safe?
- Dive without fins using only arm propulsion
- Use a zip tie as a temporary strap replacement (Correct answer)
- Borrow a single fin and mismatched-pair dive
- Cancel all remaining dives until a replacement strap is sourced
Correct answer: Use a zip tie as a temporary strap replacement
A zip tie can serve as a temporary fin strap long enough to complete planned dives safely until a proper replacement strap is obtained.
NAUI Equipment Use & Maintenance 2
After a saltwater dive, what is the most important first step when rinsing your regulator?