Underwater, your voice is useless. The moment you descend below the surface, spoken language disappears into a stream of bubbles, and your hands become your primary means of communication. Dive hand signals are not just a convenience — they are a critical safety system that every diver relies on from their very first open water certification to their thousandth dive. Misunderstand a signal, and a minor issue can escalate into a real emergency.
Whether you are a newly certified diver or brushing up before your next trip, mastering these underwater hand signals will make you a safer, more confident dive buddy. Here are the 10 essential scuba diving signals every diver must know.
The 10 Essential Dive Hand Signals
1. OK — "I'm Fine" / "Are You Fine?"
This is the most frequently used signal in diving, and it has two versions depending on whether you are on the surface or underwater.
- Underwater: Touch the tip of your thumb to the tip of your index finger, forming an "O" shape, while extending the remaining three fingers upward. This is both a question and an answer — flash it to your buddy to ask "Are you OK?" and use the same gesture to respond "Yes, I'm OK."
- Surface: At the surface, the small finger-circle is hard to see from a distance. Instead, raise one arm overhead and touch your fingertips to the top of your head, forming a large "O" with your arm and head. This is visible to boat crews and dive guides from far away.
The OK signal is the backbone of diving communication. You will use it dozens of times on every dive. When your buddy flashes it, always respond — never leave a signal unanswered.
2. Not OK / Problem
Hold your hand out flat with fingers together, palm facing down, and tilt it side to side in a rocking motion — like the gesture for "so-so." This means "something is not right." It does not necessarily indicate an emergency, but it tells your buddy that you need attention. After giving this signal, point to the source of the problem: your ear, your mask, your regulator, or wherever the issue is.
This is the single most important safety signal after OK. If you see your buddy give it, stop and help troubleshoot immediately.
3. Up / End the Dive
Extend a closed fist with your thumb pointing straight up. This is an unambiguous instruction: "We are going up." Depending on the context, it can mean "let's begin our ascent" or "the dive is over." It is not a suggestion — when any diver in a group signals thumbs up, the entire team ascends.
New divers sometimes confuse this with a "good job" gesture. Underwater, thumbs up always means ascend. If you want to say things are good, use the OK signal instead.
4. Down / Descend
The opposite of thumbs up: extend a closed fist with your thumb pointing straight down. This signals "let's go deeper" or "begin the descent." At the start of a dive, the dive leader will often give this signal after confirming everyone is ready at the surface.
5. Stop / Hold
Hold your hand up with your palm flat and facing your buddy, fingers together and pointing upward — the universal "stop" gesture. This means "hold your position, do not move." A dive guide might use it to pause the group before rounding a corner to check for current, or a buddy might use it to signal they need a moment to equalize.
6. Low on Air
Make a fist and place it against your chest, then move it slightly away and back — tapping your chest area. This means "I am getting low on air." The specific threshold depends on the dive plan, but typically divers signal this at 50 bar / 700 psi. This is a heads-up, not an emergency. It tells your buddy and dive leader that the team should start heading back or begin the ascent soon.
According to DAN (Divers Alert Network), running low on air is one of the most common contributing factors to diving incidents. Signaling early gives your team time to respond calmly.
7. Out of Air — Emergency
Draw your flat hand across your throat in a slicing motion, like a "cut" signal. This is the most urgent hand signal in diving: "I have no air and I need to share yours immediately." If you see this signal, you should present your alternate air source (octopus regulator) to your buddy without hesitation.
Practice this scenario regularly. Most dive training agencies, including PADI and SSI, require air-sharing drills as part of certification — and for good reason. The response to this signal must be automatic.
8. Look / Watch
Point your index and middle fingers at your own eyes, then point in the direction you want your buddy to look. This means "look over there." Dive guides use this constantly to point out marine life — a sea turtle drifting past, a nudibranch tucked into the reef, or a manta ray gliding overhead. When you see this signal, follow where the diver is pointing.
This is where having a capable camera setup pays off. Capturing what you spot is one of the great joys of diving, and with underwater phone housings from DIVEVOLK, you can shoot photos and video without missing a beat. The SeaTouch 4 Max lets you operate your phone's camera with tactile buttons, so you can respond to a "look" signal and start shooting in seconds.
9. Buddy Up / Stay Together
Hold up your index and middle fingers side by side, pressed together — like a "peace" sign but with the fingers touching. This means "stay close to me" or "pair up." Dive leaders use this to remind the group to tighten formation, especially in areas with current, reduced visibility, or heavy boat traffic.
The buddy system is the foundation of recreational dive safety. Never let yourself drift so far from your partner that you cannot clearly see and respond to their signals.
10. Level Off / This Depth
Hold your hand out flat, palm facing down, and move it side to side in a level, horizontal motion — like you are smoothing a tabletop. This means "maintain this depth" or "stop ascending/descending." Dive guides use it to keep the group at a specific depth during safety stops, decompression pauses, or when navigating a particular section of a wall dive.
Bonus: Advanced Dive Hand Signals
Once you have the essentials locked down, these additional signals will make your dives richer and more communicative.
Take a Photo
Hold both hands in front of your face, one flat and vertical (the "camera body") and the other curled on top (the "shutter button"), then press the curled finger down. Alternatively, simply mime holding a camera to your eye. This tells your buddy "take my picture" or "I want to photograph this." With compact setups like the SeaTouch 4 Max Kits, you can go from signal to shot almost instantly — add lenses and filters for macro critters or wide-angle reef scenes, and dive lights for bringing out true colors at depth.
Air Quantity (Showing Tank Pressure)
After getting your buddy's attention, hold up fingers to show your remaining air in tens of bar (or hundreds of psi). For example: holding up ten fingers (flash once) then five more fingers means 150 bar. Some regions use a closed fist to represent zero. This quick check keeps both divers aware of the team's air supply without requiring a slate.
Current Direction
Hold your flat hand at an angle and wave it in the direction the current is flowing, like a fish swimming through water. Some divers wiggle their fingers while sweeping their hand. This warns your buddy about current so you can adjust your dive plan — swim into the current at the start of the dive while you have energy and air, and ride it back at the end.
Marine Life Signals
Many dive communities have developed specific hand shapes to identify marine life without needing a slate:
- Shark: Place your flat hand vertically on top of your head like a dorsal fin.
- Turtle: Place one fist on top of the other and rotate your thumbs — mimicking a turtle's flippers paddling.
- Ray / Manta: Hold both arms out to the sides and wave them gently up and down, imitating a ray's wing motion.
- Octopus: Wiggle all your fingers downward from a closed hand, simulating tentacles.
- Nudibranch / Small critter: Pinch your thumb and index finger together to indicate something tiny, then point to where it is.
These vary by region, so always confirm them during your pre-dive briefing.
Regional Variations: PADI, SSI, and Local Dive Cultures
While the core signals above are nearly universal, some signals differ between training agencies and dive cultures. A few examples:
- The "low on air" signal is sometimes done by placing a flat hand on top of the head (some European agencies) rather than tapping the chest.
- Number displays can vary — some regions count on one hand starting with the thumb, while others start with the index finger.
- In cold-water diving with thick gloves, many signals are simplified because fine finger movements are impossible.
- Technical divers often have an expanded vocabulary of signals for staged decompression, gas switching, and team formations.
The golden rule: never assume your buddy uses the exact same signals you do. Review your signals together before every dive, especially when diving with new partners or in a new region.
5 Tips for Better Underwater Communication
1. Get Your Buddy's Attention First
A signal is worthless if nobody sees it. Tap your buddy's tank with a clip or pointer stick, wave your hand in their peripheral vision, or use a dive light to flash their attention. Never grab or startle another diver.
2. Make Signals Slow and Deliberate
Rushing through a hand signal defeats the purpose. Hold each gesture for a beat longer than you think necessary. Exaggerate your movements slightly. Underwater, everything looks smaller and less distinct than on the surface.
3. Agree on Custom Signals During the Pre-Dive Briefing
Before every dive, review the basics with your buddy and establish any custom signals you might need. Photographing a specific species? Agree on a gesture for it. One buddy has a history of ear trouble? Decide on a specific signal for "I need to equalize."
4. Practice in the Pool
If you are learning to dive or getting back into it after a break, practice signals in a pool or confined water setting. This is also a great time to test your gear — check that your technical support resources are bookmarked for your DIVEVOLK housing setup, and run through your camera controls so that operating them underwater is second nature.
5. Carry a Backup Communication Tool
An underwater slate, a wet-notes booklet, or even a simple dive whistle for surface signaling can fill gaps when hand signals are not enough. For complex messages — dive site directions, species identifications, or safety instructions — a slate is invaluable.
Communication Makes Every Dive Better
Diving is a team activity, and good communication is what separates a great dive from a stressful one. When you and your buddy can effortlessly exchange information — "I'm OK," "look at that turtle," "let's head back" — the entire experience becomes smoother, safer, and far more enjoyable.
Take the time to review these dive hand signals before your next trip. Practice them with your buddy. Discuss them during your briefing. The investment is tiny, and the payoff — in safety, confidence, and shared underwater moments — is enormous.
Ready to capture those moments? Explore DIVEVOLK's full range of underwater phone housings and SeaTouch 4 Max Kits to bring a camera on every dive without the bulk of traditional underwater photography gear.
