What Does the Term "Confined Water" Mean in Scuba Diving?

The term confined water is used to describe a dive site at which the environment is entirely predictable and controlled. This includes acceptable visibility for the planned dive, a calm surface and an absence of strong current. Confined water sites should have easy entry and exit points, and should not have any overhang or obstruction that prevents divers from directly reaching the surface. The most common example of a confined water dive site is a swimming pool. Other typical confined water locations include a calm bay, a lake or even a man-made quarry. Confined water sites are used for skill practice and training, for testing out new dive gear, or for novice divers who would like to play in an easy environment before heading to open water. 

A confined water dive most often refers to training dives with the express purpose of learning, practicing, and evaluating dive skills. The PADI (Professional Association of Diving Instructors) open water course, for example, requires students to pass five confined water dives at a variety of depths. Initially, skills are practiced in water shallow enough to stand up in, and as the student progresses, skills are practiced in deeper water. Any dive made in confined water, however, can be technically considered a confined water dive.