Scuba Diving Speak

When you’re underwater, you need a way to communicate. Seeing as simply talking isn’t an option, scuba divers have developed a unique set of signals and gestures to help divers and diving instructors convey essential messages to one another. These gestures are very important to learn and memorize so that you can quickly convey important information no matter what situation or state-of-mind you are in.

Like every language, divers’ lingo also has its own special scuba slang, a vocabulary that only divers know. Ready to learn some scuba diving speak? Let’s dive in.

History of Diving Communication Methods

Until the late 19th century divers communicated with the surface simply by pulling their lifeline. In 1874, Louis Denayrouze tried taking diving communication a step forward when he patented a tube system that could carry a diver’s voice to the surface, but the new system wasn’t very successful.

In the early 20th century electrical telephone wires were merged into the lifeline, and divers wore headsets or had speakers built into their helmets. Initially, this system allowed only for communication between the diver and the surface. After some adjustments were made, it became possible for divers to use the system to communicate with each other as well.

While large-scale commercial diving excursions utilize these sophisticated voice communication systems, recreational divers do not. We rely on non-verbal communication methods — hand gestures, writing slates and light signals — to communicate with each other underwater.

Hand Signals

The most common way to communicate underwater is with hand signals. While this technique does require a clear line of sight, it has many advantages. It’s simple, easy to remember and reliable. Scuba diving hand signals are also universal, after all, it is an international sport. So, no matter where you take your beginners level diving classes, you will learn the same set of hand signals, which were approved by the Recreational Scuba Training Council. Here are some basic signals you may find useful when you dive:

I’m Out of Air: flatten your hand and bring it across your throat, as if slicing.

Slow Down (or Relax/Take It Easy): make slow up-and-down movements with a flat hand, palm down.

Go That Way: make a fist, and use your thumb to point in the direction everyone is supposed to go.

I’m Descending/Descend: this gesture is like giving directions. Make a fist, and point down with your thumb.

Something’s Wrong: open your hand, spread your fingers, and rock your hand back and forth, palm down.

Scuba Jargon

Scuba diving also has its own vocabulary or slang that is used by divers all around the world. Don’t worry, these phrases will also be covered in your scuba diving classes. Here are a few examples:

Backroll: entering the water back first off the side of the boat.

Boat Dive: any scuba dive that requires a boat to take you to the dive site.

C-Card: this is the proof that you have completed your training course. You’ll need to show it before you can dive in open water without an instructor.

DPV: an acronym for Diver Propulsion Vehicle, a motorized device that helps divers move quickly underwater.

No Fly: this is the recommended length of time between your dive and when it is safe to get on an airplane.

Squeeze: the discomfort or pain associated with the change in pressure underwater (often felt in mask, ears and other enclosed areas).

Viz: how far ahead of you can see clearly underwater.