IDC Dive Equipment & Technology

Question 1

What is the primary purpose of the BCD (Buoyancy Control Device) in scuba diving?

Accepted Answer

To allow the diver to control buoyancy at depth and at the surface by adjusting the volume of air in the bladder

Answer

To keep the diver warm in cold water

Answer

To hold the scuba tank on the diver's back only

Answer

To protect against decompression sickness

Question 2

What is the function of the first stage of a scuba regulator?

Accepted Answer

To reduce tank pressure to an intermediate pressure for delivery to the second stage

Answer

To deliver air directly to the diver's mouth at ambient pressure

Answer

To monitor remaining air pressure in the tank

Answer

To control the flow of air to the BCD inflator

Question 3

What is the purpose of the alternate air source (octopus) in recreational scuba diving?

Accepted Answer

A secondary second stage for sharing air with an out-of-air buddy

Answer

A backup regulator for the diver to use themselves if their primary fails

Answer

A pressure gauge for monitoring air supply

Answer

A device for inflating the BCD underwater

Question 4

How does a wetsuit provide thermal protection for divers?

Accepted Answer

By trapping a thin layer of water next to the skin which is warmed by body heat

Answer

By keeping the diver completely dry and preventing water contact with the skin

Answer

By circulating heated air through tubes in the suit

Answer

By reflecting body heat back toward the diver

Question 5

What information does a Submersible Pressure Gauge (SPG) provide to a diver?

Accepted Answer

The remaining air pressure in the scuba cylinder

Answer

The depth of the current dive

Answer

The water temperature at current depth

Answer

The diver's decompression status

Question 6

What is the difference between a cylinder's 'working pressure' and 'test pressure'?

Accepted Answer

Working pressure is the normal fill pressure; test pressure is the higher pressure used during hydrostatic testing

Answer

They are identical values used interchangeably

Answer

Working pressure is for open water; test pressure is for pool use only

Answer

Test pressure is lower than working pressure for safety