“Cavern diving” is defined as diving that takes place within sight of a natural light source (the sun) and within 200 linear feet of an open water surface. The Cavern Diver course is an entry-level program to the overhead environment. It is a comprehensive three-day program designed to develop the minimum skills and knowledge for cavern diving and describes the dangers involved with cave diving. Conservation, dive planning, environment, procedures, techniques, problem solving, and other specialized needs of cavern diving are covered.

Cavern diving skill development includes body positioning (trim); buoyancy control; emergency procedures; line following; the use of reels; propulsion techniques; silting; entanglement; disorientation; and equipment modifications.