Certified Hyperbaric Technologist Practice Test

Which of the following is NOT a piece of equipment that allows human underwater breathing?

1. Scuba equipment

2. Diving bells

3. Air balloons

4. Self-contained underwater breathing apparatus (SCUBA)

The correct answer is: Air balloons

The correct answer is identified as "air balloons" because they do not allow for human underwater breathing. Scuba equipment, diving bells, and self-contained underwater breathing apparatus (SCUBA) are all specifically designed to facilitate breathing while submerged in water. Scuba equipment includes various apparatuses like tanks and regulators that provide a supply of compressed air for divers to breathe underwater. Diving bells are sealed containers that can descend underwater and provide a breathable atmosphere by utilizing atmospheric pressure, allowing divers to enter and exit while remaining submerged. In contrast, air balloons are not designed for underwater use or to support breathing in a submerged environment. They operate on principles of buoyancy and are meant for floating in the air, not for facilitating respiration underwater. Thus, air balloons do not accommodate the need for humans to breathe while submerged, making them the correct answer.