Dive Equipment & Technology Flashcards

What is the correct procedure for assembling a scuba unit (regulator and BCD onto a tank)?

Answer: Check the O-ring, attach the first stage to the tank valve, turn on air slowly and check for leaks, secure the BCD to the tank, connect the inflator hose

Proper assembly involves inspecting the O-ring, attaching the first stage, opening the tank slowly, checking for leaks, securing the BCD to the tank, and connecting all hoses.

Which connection type is generally considered more reliable for high-pressure scuba tanks — DIN or yoke (A-clamp)?

Answer: DIN is generally considered more reliable because the O-ring is protected inside the fitting, reducing the risk of blowout

DIN connections are considered more reliable because the O-ring is captured inside the DIN fitting, protecting it from displacement and reducing high-pressure blowout risk.

What is the purpose of the 'J-valve' on older scuba tanks and why has it been largely replaced?

Answer: A reserve valve that delivered a breathing resistance signal when approximately 50 bar remained — replaced by the SPG as a more reliable air management tool

J-valves had a spring-loaded mechanism that increased breathing resistance at low pressure (~50 bar), warning the diver to access their reserve air. SPGs made this obsolete.

In what diving scenarios is a dive light particularly valuable according to PADI training?

Answer: Useful for night diving, cavern and overhead environments, exploring dark areas, and restoring colors absorbed by water at depth

Dive lights are essential for night diving and overhead environments, and they also restore colors absorbed by water at depth, enhancing visibility and marine life appreciation during all dives.

What is the importance of buoyancy control in preserving coral reef environments?

Answer: Poor buoyancy causes divers to contact, break, and damage fragile coral — neutral buoyancy prevents reef damage

Poor buoyancy control is a leading cause of reef damage by divers — breaking coral, stirring up sediment, and disrupting marine life habitats. Neutral buoyancy is the core environmental skill.

What is a drysuit and under what water temperature conditions should it be considered?

Answer: A suit using seals at neck and wrists to keep the diver dry, using trapped air or an undergarment for insulation — recommended below approximately 10-15 degrees Celsius

A drysuit keeps the diver completely dry by sealing at the neck and wrists; insulation comes from a dry undergarment or trapped air — appropriate for cold water typically below 15 degrees Celsius.