Military diving in the context of Underwater search and recovery

Professional diving is underwater diving where the divers are paid for their work. Occupational diving has a similar meaning and applications. The procedures are often regulated by legislation and codes of practice as it is an inherently hazardous occupation and the diver works as a member of a team. Due to the dangerous nature of some professional diving operations, specialized equipment such as an on-site hyperbaric chamber and diver-to-surface communication system is often required by law, and the mode of diving for some applications may be regulated.

There are several branches of professional diving, the best known of which is probably commercial diving and its specialised applications, commercial offshore diving, inshore civil engineering diving, marine salvage diving, hazmat diving, and ships husbandry diving. There are also applications in scientific research, marine archaeology, fishing and aquaculture, public safety, law enforcement, military service, media work and diver training.

Underwater warfare, also known as undersea warfare or subsurface warfare, is naval warfare involving underwater vehicle or combat operations conducted underwater. It is one of the four operational areas of naval warfare, the others being surface warfare, aerial warfare, and information warfare. Underwater warfare includes:

• Actions by submarines actions, and anti-submarine warfare, i.e. warfare between submarines, other submarines and surface ships; combat airplanes and helicopters may also be engaged when launching special dive-bombs and torpedo-missiles against submarines;
• Underwater special operations, considering:
  • Military diving sabotage against ships and ports.
  • Anti-frogman techniques.
  • Reconnaissance tasks.

The Fuerzas Especiales (Special Forces), commonly known as FES is a special operations group of the Mexican Naval Infantry Corps (the 'Mexican Marines') under the Mexican Navy, established in 2001. Within the Naval Infantry Corps the FES falls under the Mexican Navy Special Operations Unit (UNOPES) which additionally includes various Naval Infantry Corps commando and airborne units.

FES personnel are capable of carrying out non-conventional warfare in the air, sea and land, using all means of infiltration available to develop the most variable operational incursions with the use of military diving techniques, parachuting, vertical descent, urban combat, sniping and use of explosives. The units are well organized, trained and equipped to operate independently in maritime, lake, riverine or terrestrial scenarios.