Many signals vary across the world and across diving Agencies. If diving with strangers it is a good practice to agree on the signals you will use prior to the dive.

Introduction

Communicating underwater is an important skill to learn and can lead to a whole lot of confusion is it is not done well. With rebreathers and full face masks it is possible to have a reasonable verbal conversation, however for the rest of us, it's a wide assortment of hand signals or writing on a slate.

Hand signals are always responded to (usually with OK) so that both buddies know they have successfully communicated. Lack of response may mean the buddy has lost concentration, has something wrong, is cold on the way to hyperthermia, narcosed at depth or just plain rude!

When using hand signals underwater, they are usually done in front of the chest and generally require a response from whom you are communicating. They should be performed clearly, positively and strongly. Lethargic, slow or inappropriate signals could be an indication that something is wrong.

When night diving, be sure to shine your torch on your hand signals and of course never shine the torch in other divers eyes, else you will damage their night vision for some time. Attract attention by moving the light beam from side to side preferably within your buddies field of vision.

Basic Signals

(Are you) OK?	OK on the surface

Stop, wait here	Slow down, move hand slowly down and up a few times

Stay at this depth. Move hand left to right and back	Up	Down

Stay together	Move apart a little	You lead, I'll follow

Where is your Buddy?

You	Me	Come here, beckon

Distress Signals

Not OK, something is wrong. rotate wrist slightly a few times Then point to whatever is the problem e.g., mask or ear.	Out of Air (BSAC) Move hand forward and down at 45 degrees.	Out of Air (PADI) Move hand across the neck left to right a few times.

Distress on the surface. wave aggessively	Cramp - tight fist then point to where	I'm Narked! Move index finger in circles.

I am cold, move hands up and down	I am out of breath, move hands in and out at chest level.

Air Related

How much air do you have?	Response example 1 50 Bar followed by 20 Bar - 70 Bar (Always round down to the nearest 10)

How much air do you have?	Response example 2 Repeat the 50 Bar signal twice + 30 Bar = 130 Bar (Always round down to the nearest 10)

On Reserve or 50 Bar	repeat signal twice = 100 Bar	Occasional signal for 100 Bar

Depth and Time Related Signals

Ascend to a particular depth Depth signalled afterwards e.g., 6m

Descend to a particular depth Depth signalled afterwards e.g., 10m

Time	Stop for 3 Minutes	Time out (sometimes used to denote 100 Bar)

Directional Signals

That way, point hand in the direction	Home	I don't know, shrug shoulders

Training Signals

Look	at me	I'm in Charge (Sergeant Stripes)

Underwater Creatures

Turtle, wiggle thumbs	Large Ray , flap fingers like a large ray	Moray Eel

Lobster	Hammerhead

Shark	Lionfish

Other Signals

Do not touch, move top hand down to end a few times	Boat

Safety in Diving