Communicating Underwater

Using full face masks in diving allows you to use radio communication

Using full face masks in diving allows you to use radio communication.

One of the joys of diving is that one cannot talk underwater, this means that those annoying non-stop-talking individuals cannot bother you. However, there are from time to time instances when you will want/need to communicate with your buddy or other divers. There are several different ways to do this.


That’s right, the most important part of communicating underwater is deciding how you will communicate underwater before you are underwater. Make sure that you have the correct equipment and that you know how to use it. Talk through your dive plan. Make sure that you are happy with everything that you are going to do.


Sound travels 4 faster underwater than it does on the surface. This means that it can be difficult to determine where sounds have come from. Also it is not possible to speak underwater due to our mouths being filled with a regulator. So most sounds underwater are just used to get the attention of someone. I have seen it done several different ways. Firstly, there is the good old tank banger. This is something that you use to bang the tank with to make a tapping sound. There are shakers. These are just like maracas and you shake them (surprisingly enough) to get the attention of other divers. Finally there are squawkers. These are air horns that attach to your LPI and can be used underwater to make a squawking sound.

All of these are useful in attracting the attention of other divers. I personally use a double-ended p-clip to tap on the tank. I have never purchased a dedicated tank banger as it can be accidentally be left behind on your rental cylinder. The shakers and squawkers just seem like an unnecessary expense.

There is one other sound method that I haven’t discussed and that is the use of radio. As technology has advanced it has now become possible to use radio communication systems underwater. However, these cannot be used with a normal mask and regulator. You have to use them with a full face mask like the Ocean Reef Neptune, which I tried out back in 2013. It was a fun experience but I have never taken one out on a full dive. The RRP is $600+ so it is definitely a large investment just for the mask, and then the communication system is extra. Also you will need a buddy who has the same .

Hand Signals

From the moment you entered into your first scuba diving class your instructor probably started introducing you to hand signals. There are a lot of them. Some that you will never need to know and some that you really should. I am not going to go through all of the signals that you could know but here is a brief list of the most common ones.

Common scuba diving hand signals

Common scuba diving hand signals

Make sure that you know your hand signals as they are the primary means of communication underwater. You should practice them frequently so that you don’t forget them. But if you have a brain fart and forget what they signals are, you could always resort to writing down what you want to say.


Sometimes you just have too much to say or you’ve forgotten how to signal it. This is where a slate or wet notes come into the equation. Having these on you allows you to ask questions or give detailed information. It also allows you to sketch wrecks and make navigational notes.


If you look at any advanced diver they will be carrying a torch. Mainly used for seeing on night dives or inside areas where light doesn’t penetrate, a dive light can be a very useful thing even on a day time dive. There are two main signals that you can make with a light. The first is the OK. This is doing by circling the light in a controlled manner. As with the hand signals it is a question and an answer. There is also the “attention” signal. This is a rapid movement back and forth of the light. Hopefully your buddy should see that you are in trouble and you can then signal


Finally the last method of communication is touch. This is really reserved for those dives where visibility is going to/could be a problem (eg penetration diving, or diving in the UK). Discuss with your buddy and make sure that you both know what the touch signals that you will use mean. Practice them before hand so that they are second nature. It is unlikely as an Open Water diver you will be face with a zero-visibility situation and if you are you should probably surface and end the dive – what’s the point diving if you can’t see the fish?

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