Diver Communications

Diver communications are the methods used by divers to communicate with each other or with surface members of the dive team.

There are several distinct forms of diver communications:

  • Voice communications - Most professional diving equipment such as full face diving masks and diving helmets include voice communication equipment
  • Video communications - Surface supplied divers often carry a closed circuit video camera on the helmet which allows the surface team to see what the diver is doing and to be involved in inspection tasks. This can be used to transfer signals to the surface if voice comms fails, and is in itself a one way mode of communicating useful data to the surface.
  • Text communications - Underwater slates may be used to write text messages which can be shown to other divers, and there are some dive computers which allow a limited number of pre-programmed text messages to be sent through water to other divers or surface personnel with compatible equipment.
  • Non-verbal communications:
    • Hand signals - Recreational divers do not usually have access to voice communication equipment, and it does not generally work with a standard scuba demand valve, so they use other signals. Hand signals are generally used when visibility allows, and there are a range of commonly used signals, with some variations. These signals are often also used as an alternative by professional divers
    • Line signals (rope pulls) - Rope signals can be used if the diver is connected to another diver or tender by a rope or umbilical. There are a few partly standardised codes using "pulls" and "bells" (a pair of short tugs). These are mostly used as backup signals by professional divers in the event that voice communications fails, but can be useful to recreational and particularly technical divers, who can use them on their surface marker buoy lines to signal to the surface support crew.
    • Light signals - Made using an underwater torch at night. There are not many standard light signals. Suitably skilled divers can transmit morse code using a light.
    • Cave line symbols - these are symbols attached to cave lines, indicating critical information such as the direction to the exit.
    • Sign language Divers who are familiar with a sign language such as American sign language and equivalents may find it useful underwater, but there are limitations due to the difficulty of performing some of the gestures intellibly underwater with gloved hands and often while trying to hold something.
    • Tap codes - made by knocking on the walls, are used occasionally to communicate with divers trapped in a sealed bell or the occupants of a submersible during a rescue.
    • Rattle - a tube containing ball bearings used by guides of large groups to attract attention.
    • Miscellaneous emergency signals - Including the use of mirrors, compressed air sirens, whistles, noisemakers, colour coded Delayed Surface Marker Buoys etc., to alert the surface support personnel of a problem
    • Diver down signals - The dive flags, lights and shape signals used to indicate the presence of divers in the water.

Read more about Diver Communications:  Voice Communications, Hand Signals, Torch / Flashlight Signals, Rope Signals, Cave Line Symbols, Miscellaneous Emergency Signals