plongee

Plongée is the act or practice of descending and staying underwater, typically for exploration, work, photography, or sport. In French usage, plongee covers underwater diving in general, including scuba diving (plongée sous-marine) and freediving (plongée libre).

Common forms include recreational diving, technical diving, commercial diving, and military diving. Freediving is performed on breath holds with no breathing apparatus. Specialized forms include cave diving, wreck diving, and underwater surveying.

Most recreational plongées use scuba equipment: a compressed gas cylinder, a regulator to deliver breathable gas, a buoyancy compensator, a mask, fins, and an exposure suit. Freediving relies on breath control and minimal equipment. Some professional diving uses surface-supplied gas and helmets or full-face masks.

Training and certification are typically required for safe diving. International agencies such as PADI, NAUI, SSI, and CMAS offer courses covering theory, skills, and safety procedures. Certifications increase with depth, gas mixtures, and complexity of diving.

The modern practice has roots in early underwater exploration and surface-supplied diving, with the development of scuba gear in the mid-20th century. The Aqua-Lung, developed by Jacques-Yves Cousteau and Emile Gagnan in 1943, helped popularize recreational plongée.

Safety and environmental considerations are central. Divers learn buoyancy control, gas management, risk awareness for decompression and nitrogen narcosis, and ways to minimize impact on marine life.