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Apnea TrainingSometimes with scuba diving, not everything always goes exactly as planned. You may surface a distance away from your surface level. There may be other boats in the area that aren’t aware of your presence. Or a multitude of other things can go wrong during a dive.

That’s what makes surface detection devices so valuable to divers. These are tools divers use to notify others of their presence, whether it’s their own dive team or somebody else.

Purpose of Surface Detection Devices

Surface detection devices can be used to tell the support boat where you are after you rise to the surface after a dive. They also can help prevent you from being struck by a boat while you are in the water.

They can mark your location with you are drift diving or while at a decompression stop. Or they can help rescue services in lifeboats and helicopters locate you if you are stranded or blown off course.

Types of Surface Detection Devices

One of the most widely used surface detection devices is the surface buoy marker. This includes decompression buoys and are sometimes called the “safety sausage” or the blob.

Red, collapsible flags are known as “diver down flags” because they are highly visible. Usually, you will find these flags attached via a bungee cord to a sealed cylinder that floats.

High-pressure whistles can be made of either metal or plastic. But they are ideal for notifying people far away that you are in the area. But blow hard because usually you are trying to be heard over the engine noise.

Common Safety Equipment

If you are diving at night or near nightfall, it’s a good idea to carry a flashlight or strobe light.

Orange water dye is sometimes used by divers to let rescuers in helicopters know their location, as are red pyrotechnic flares.