What is the primary purpose of a buoyancy compensator (BC)?

The primary purpose of a buoyancy compensator (BC) is to help divers manage their buoyancy underwater, allowing them to achieve and maintain neutral buoyancy during the dive. Neutral buoyancy is crucial as it enables divers to float effortlessly in the water column without rising or sinking, which allows for ease of movement and stability while observing marine life or conducting tasks.

Additionally, a BC provides surface flotation, assisting divers in staying afloat at the surface when they are not submerged. This is especially important during surface intervals or emergencies. Furthermore, the BC plays a vital role in controlling ascent and descent rates by allowing divers to adjust the volume of air within the bladder of the BC. By adding or releasing air, divers can manage how quickly they ascend or descend, promoting safety and comfort throughout their dive.

Considering all of these functionalities, the answer encompasses the various essential roles that a buoyancy compensator plays in dive safety and performance.