SCUBA Diving Supervisor Practice Test

Boyle's Law states that the volume of a gas is inversely proportional to its pressure when the temperature is held constant. This means that as pressure increases, the volume decreases. In practical terms, if you take a gas and compress it by increasing the pressure applied, the space that the gas occupies (its volume) will become smaller.

For divers, this principle is significant when considering gas behavior during ascents and descents. As a diver goes deeper underwater, the pressure increases due to the weight of the water above, resulting in a decrease in the volume of any air-containing spaces, such as the lungs or the buoyancy control device (BCD). Understanding this relationship helps divers manage buoyancy and avoid problems such as barotrauma. Thus, the correct answer reflects the behavior of gas under increased pressure at a constant temperature, aligning with the physical principles outlined in Boyle's Law.