Scuba Diving Hand Signals Written by: Alex Jones Created: 04/25/2025 Updated: 02/15/2026

You can’t communicate with words underwater. When you want to ‘talk’ with your dive buddy, you need to use hand signals, a common language that you both understand.

These standardized gestures are the universal language of diving. They even let divers from different countries, backgrounds, and training organizations communicate clearly and effectively underwater.

So, let’s take a look at the diving hand signals every diver needs to know, from basic safety communications to specialized signals for marine life encounters and photography. These signals can make your scuba diving safer and more enjoyable.

Why Hand Signals Matter for Diving Safety

Underwater communication isn't just a convenience — it’s the best way to keep you safe when you dive. Effective communication between dive buddies is great for:

• Sharing important information about scuba equipment status
• Warning about potential hazards
• Coordinating movements and navigation
• Communicating physical or psychological concerns
• Sharing exciting marine life sightings
• Managing emergency situations

While some advanced divers use underwater writing slates or specialized underwater communication devices, hand signals are the primary and most reliable method of communication.

They work regardless of technology failures

Unlike electronic communication devices, hand signals don't rely on batteries or equipment that can malfunction.

They are universally understood

Most basic diving signals are standardized across training agencies and geographical regions.

They are immediate and attention-grabbing

A clear hand signal can quickly alert your buddy to important information without delay.

Essential Safety and Status Signals

The fundamental OK signal

The most frequently used diving signal is the "OK" sign, formed by connecting the thumb and forefinger in a circle with the remaining fingers extended. This signal says:

• As a question: "Are you OK?" when directed at another diver
• As a response: "I am OK" when given after being asked
• As confirmation: "OK to descend/ascend"
• As a general status update during the dive

The surface OK signal

Since the standard hand signal may not be visible to distant boats, the surface OK is performed by touching hands above the head in a large circle or by extending one arm straight up. This confirms your status after surfacing.

Directional signals

• Directional indication: Point with the entire hand in the direction you want to go.
• Level off: Hold your hand flat, palm down, and move it horizontally.
• Go up/ascend: Thumb up with the hand closed.
• Go down/descend: Thumb down with the hand closed.
• Turn around: Make a circular motion with your extended forefinger.

Air and pressure status

• How much air?: Tap your tank or gauge location to ask about remaining supply.
• Air supply status: Show a closed fist for each 1000 PSI/70 bar, then fingers for hundreds.
• Low on air: Rock a flat hand back and forth at chest level.
• Out of air: Move a flat hand across your throat in a cutting motion. This indicates an immediate need for your buddy's alternate air source.

Problem indication and assistance

• Something is wrong: Rock a flat palm side to side.
• I'm cold: Cross your arms in a hugging motion.
• Cramp: Make a fist and grasp it with the other hand.
• Danger: Tap the top of your head with a closed fist.
• Emergency/Panic: Wave both arms overhead at the surface or underwater.

Dive progress and planning signals

• Safety stop: One hand flat (palm down) with the other hand's fingers spread above it (forming a roof).
• Slow down: Move palms toward and away from each other slowly.
• Look/Pay attention: Point with two fingers from your eyes toward the object.

Marine Life Encounter Signals

• Shark: Flattened hand on top of the head (like a fin).
• Turtle: Stack fists and move them in a swimming motion.
• Ray/Manta: Cross wrists and "flap" hands like wings.
• Octopus: Bunch hand then spread fingers repeatedly.
• Lionfish: Spread fingers and move hand downward.

Specialized Signals

Photography signals

• Take my picture: Frame with thumbs and index fingers.
• Wait for photograph: Hold up one index finger.

Technical diving signals

• Switch gases: Mime reaching to valve or switching at chest level.
• Perform gas check: Tap the tank or regulator.

Final Tips for Clear Communication

• Make signals deliberate: Use defined movements in your buddy's line of sight.
• Confirm understanding: Always answer a signal with an "OK" once understood.
• Practice on land: New divers should practice until signals are second nature.

Hand signaling is the common language of discovery. Learn it, practice it, and stay safe!