Underwater search and recovery

Underwater search and recovery is the process of locating and recovering underwater objects, often by divers. but also by the use of submersibles, remotely operated vehicles and electronic equipment on surface vessels.

Most underwater search and recovery is done by professional divers as part of commercial marine salvage operations, military operations, emergency services, or law enforcement activities.

Minor aspects of search and recovery are also considered within the scope of recreational diving.

The scope of professional search and recovery includes the following applications:

Search and recovery diving is also frequently undertaken as part of recreational diving, and most diver training organisations have dedicated training courses on the subject. Search and recovery is generally considered a more hazardous speciality diving course.

Underwater search and recovery used to form a mandatory component of the Advanced Open Water Diver training course for many North American diver training agencies, which, in addition to learning basic search and recover skills, also assisted in teaching students to cope with task loading.

Although the scale, value and equipment used in commercial and recreational search and recovery are enormously different, the basic premise remains the same in each case.

Underwater searches, much like above water searches, are designed around specific search patterns. The most common forms of underwater search patterns are:

The patterns are usually performed by divers in pairs or teams below the water, but they can also be conducted by use of a tender who may be a snorkeller at the surface, a person on a towing boat, or a person located on the shore.

In simple search operations, the patterns will usually be conducted by the divers simply looking visually for the object. In more sophisticated search operations, underwater magnetometers or hand held sonar may be used.

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