Diver rescue

Diver rescue, following an accident, is the process of avoiding or limiting further exposure to diving hazards and bringing a diver to a place of safety. A safe place is often a place where the diver cannot drown, such as a boat or dry land, where first aid can be administered and from which professional medical treatment can be sought. In the context of surface supplied diving, the place of safety for a diver with a decompression obligation is often the diving bell.

Following rescue, it may be necessary to evacuate the casualty to a place where further treatment is possible.

There are many reasons why a diver may need rescue. These generally imply that the diver is no longer capable of managing the situation. Scenarios requiring rescue include:

The diver may get into a situation requiring rescue through incompetence, unfitness or bad luck.

The effort and difficulty of a rescue varies widely and depends on many factors such as the nature of the problem, the underwater conditions and the type and depth of the dive site. A simple rescue could be to tow to safety a diver on the surface who is exhausted or suffering from leg cramps. A complex and high-risk rescue would be to locate, free and bring to the surface a lost diver who is trapped underwater in an enclosed space such as a shipwreck or cave with limited breathing gas supplies.

The sequence of potential activities needed in a generic rescue are:

Before any attempt to perform a rescue can be made, a person or group of people who are in a position to initiate appropriate procedures must be aware of the need. This may seem an obvious requirement, but many diving fatalities occur without anyone knowing that there is a problem, and in many others the problem is initially the loss of information regarding the current status of the diver. This is common in scuba accidents, where separation of the diving team members is often the first indication of a potential problem, and many emergencies are first recognised when a diver fails to surface at the expected time.

Scuba divers generally have no voice communication and are generally restricted to visual signalling. this is limited by line of sight and visibility, which may be poor. In some cases scuba divers may be connected by a tether, or buddy line, which allows communication by line signals, and professional scuba divers often tow a surface marker buoy, which may be used to transmit a very limited range of signals to surface personnel, mainly location of the diver, and if the diver needs help.

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