PADI Equipment Knowledge & Maintenance 3

Question 1

What is the correct procedure for rinsing a regulator after a saltwater dive?

Accepted Answer

Soak and rinse with fresh water without pressing the purge button, keeping the dust cap in place

Answer

The dust cap must be in place and the purge button must NOT be pressed during rinsing to prevent water from entering the first stage.

Question 2

A diver notices their SPG reads lower than expected at the start of a dive. What is the most likely explanation?

Accepted Answer

The cylinder was not fully filled or gas was lost from a leaking valve

Answer

An unexpectedly low SPG reading at dive start almost always indicates the cylinder was not topped off or gas escaped through a leak.

Question 3

Why are aluminum scuba cylinders anodized on the exterior?

Accepted Answer

Anodizing creates a hard oxide layer that resists corrosion and surface abrasion

Answer

Anodizing converts the outer aluminum surface into aluminum oxide, which is harder and far more corrosion-resistant than bare aluminum.

Question 4

Which component in a BCD oral inflator allows the diver to add air by mouth without it escaping back out?

Accepted Answer

A one-way check valve inside the mouthpiece assembly

Answer

The one-way check valve allows air to enter the bladder from the mouthpiece but prevents it from flowing back out during exhalation.

Question 5

What is the purpose of a drysuit's non-return valve (inflator valve)?

Accepted Answer

It allows gas to enter the suit for thermal insulation and prevents backflow into the cylinder hose

Answer

The non-return (check) valve on a drysuit inflator port allows gas from the cylinder to enter the suit but blocks backflow toward the regulator.

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