As dive safety equipment goes, surface signaling devices are among the most important items to carry. Without good methods for signaling, your chances of surviving an accident that leaves you floating alone on the ocean’s surface are minimal. Here, we’ll take a look at four basic types of surface signaling devices.
Audible Surface Signaling Devices
The ocean is a quiet place and sound carries well, particularly when would-be rescuers are listening for the sound of a lost diver calling for help. An emergency whistle is a definite must-have; its sound will carry much further than your voice. Better yet is a compact pneumatic horn. This device can be heard from over a mile away, while a quality whistle can be heard from about half a mile away. A cheap whistle only carries about a quarter mile.
Operating a compact pneumatic horn is simple. It is installed between your BCD’s power inflator and low pressure hose. When you push the button, a small burst of air from your tank creates a piercing sound that’s just about impossible to miss.
Visual Surface Signaling Devices
The safety sausage or safety tube is a simple yet effective surface signaling device that takes up only a little space in a pocket. Purchase the widest, longest safety sausage you can carry, and choose the brightest color available. Different colors are more easily seen in varying weather conditions; fluorescent yellow is best for overcast weather, while orange is easier to see in sunny weather. Carrying both colors and inflating both in the event of an emergency will increase your chances of being spotted.
In the event you are lost or find yourself drifting away from the dive boat, don’t wait to deploy your safety tube. These devices are visible from as far as a mile away under ideal conditions, but in many cases, you could be out of sight range in just a few short minutes.
Signal mirrors are compact and easy to use. Pick one that has a central sight that shows the reflection the mirror casts as a red spot when you look through the sight. When signaling, aim directly for the vessel whose attention you are attempting to attract. Flash as rhythmically as possible to ensure those who see the reflections understand that someone is attempting to get their attention.
Electronic Surface Signaling Devices
There are a number of new electronic signaling devices available. Some are simply GPS personal locater beams; others incorporate a VHF radio that will allow you to speak either to your dive boat or to potential rescuers, including the Coast Guard. Learn about VHF channels and how to use them; in addition, be sure to check your batteries before each dive. Some of these units are fully waterproof; others are water resistant. The second type must be carried in a dry box and used at the surface.
Nighttime Surface Signaling Devices
Any light or chemical stick will help potential rescuers see you if you’re floating on the water’s surface after dark. A strobe light that can be mounted atop a signal tube is your best bet; combining steady lights and strobes will enhance your chances of being seen even more.
To maximize your chance of being rescued in the event you’re ever adrift, dive with multiple signaling devices. Sounding an audible signaling device while using visual signaling devices can help attract attention to your plight, so pull out all the stops if you ever find yourself in need of assistance. To paraphrase Franz Kafka’s famous saying, it’s better to have safety items on hand and not need them, than to need them and not have them available.