Hand signals help scuba divers communicate when they cannot speak normally underwater. The exact signals can vary by region, training agency, and situation, so review them with your buddy and agree on any signals you plan to use before entering the water.
Signals every buddy team should review
- OK: A recognized OK hand signal asks or indicates that a diver is okay. The response should be clear and acknowledged.
- Problem / not OK: Use the signal taught in your course to show that something is wrong, then indicate the problem if you can do so safely.
- Ascend: Agree on the standard signal for ending the dive or moving toward the surface.
- Descend: Agree on the signal used when beginning or continuing a descent.
- Low on gas / out of gas: Know the distinct signals taught for low gas and an out-of-gas emergency. Do not confuse them; practise the appropriate response during training.
- Stop / wait: Use your training’s signal to pause movement or ask a buddy to wait.
- Look / direction: Agree how you will indicate an object, animal, direction, or point of interest.
Signals are only useful when everyone understands them
Never assume another diver knows an improvised gesture. Review hand signals during the pre-dive briefing, including emergency signals and how you will communicate in poor visibility or at night. A torch, slate, or other tool may be used in some circumstances, but use it as taught and keep the team together.
What if you do not understand a signal?
Do not guess. Get the diver’s attention safely, repeat the agreed “not understood” or “problem” signal taught in your course, and follow the team’s plan. If communication fails or a diver appears distressed, respond according to your training and prioritize a controlled end to the dive when needed.
Bottom line
Hand signals are part of a larger communication plan, not a replacement for buddy awareness, dive planning, or training. Review signals before each dive, especially when diving with someone new, and follow the procedures taught by your training agency.
Essential scuba diving hand signals to review
Because spoken conversation is not practical underwater, scuba divers use agreed hand signals to share information with a buddy or guide. Common signals communicate that everything is okay, indicate a problem, ask about air supply, request an ascent or descent, or show that the dive is ending. Signals can vary by region, training agency, or team, so a pre-dive briefing is important even for experienced divers.
Review signals before entering the water
Agree on the signals you will use for low gas, turning the dive, sharing air, a lost buddy, and emergencies. Make sure both divers understand how to get attention and what response is expected. In low visibility or at night, signals may need to be delivered close enough to see clearly, with a torch used according to training. Do not assume a gesture has the same meaning to every diver.
Good underwater communication habits
Make signals deliberate and visible, then wait for acknowledgement. If you do not understand a signal, ask for clarification rather than guessing. Maintain buddy contact and use your dive computer and gas gauge as well as communication. Practising signals on land and during training helps make them easier to remember when conditions are busy or stressful.