PADI Surface Marker Buoy Diver
Career Development Center Oceans 5 offers the PADI Surface Marker Buoy Diver Specialty- and Instructor Specialty course the whole year through.
Used both in scuba diving and free diving, surface markers are a very handy and important piece of equipment. Surface marker buoys can be used to mark an area, though in most cases they are deployed to mark the position of a diver/buddy team.
There are two different types of surface markers:
- Surface Marker Buoys (SMB’s)
- Delayed Surface Marker Buoys (DSMB’s)
SMB’s are floated on the surface throughout the dive. Usually the person who leads the dive holds a reel with plenty of line that is connected to the buoy. This way it’s very easy for a boat to continuously monitor the position of the divers. In remote areas far from shore or in environments where currents are strong or conditions are rough an SMB is probably the safest way to conduct dives. In some countries (like Mozambique) it’s even a general rule or local law to dive with an SMB.
SMB’s come in different sizes, shapes and materials. Inflatable buoys that are sealed off by a cap or valve, often with a dive flag on top are quite common. SMB’s can also be made of a solid buoyant material. Inflatable or not, SMB’s are always brightly colored to ensure that surface support can easily spot the surface marker. Common colors are red and orange.
DSMB’s are inflatable signal tubes that are deployed under water usually towards the end of a dive, warning boat traffic of the presence of divers and to ensure a safe ascent. In technical diving DSMB’s are also referred to as decompression buoys. The shape of a DSMB is that of a long tube, making it easy to roll up and carry it during a dive and when it is deployed it becomes very visible when the diver pulls on the line and the tube is in an upwards position. Usually DSMB’s come in a red/orange highly visible color. Dual colored or yellow deco buoys usually serve as a signal indicating something is wrong and the divers require surface support to take action.
Although the shape of DSMB’s is usually quite the same, the design however can be very different:
Open ended: a signal tube with a slightly weighted open end to keep the open end in a downward position preventing the air escaping while being deployed.
Open ended self sealing: a signal tube that seals itself at the bottom when the air expands during ascent.
Sealed: signal tubes with either and inflation valve or a built in air supply and a pressure relief valve.
Divers and DSMB’s
Most problems with surface markers, and more specifically DSMB’s, occur during deployment. A sudden change in buoyancy, a reel jamming or equipment getting entangled in the line are just a few examples of common encountered problems. It is very important to use proper techniques and deploy cautiously to avoid an uncontrolled ascent.
During the PADI Surface Marker Buoy Specialty training divers learn a variety of techniques in order to deploy DSMB’s in a safe and easy manner. Candidates also get to work with different types of DSMB’s to experience handling different types. Next to the deployment of DSMB’s, we will also focus on how environmental conditions (current) determine the use of a surface marker. Also using an SMB/DSMB as descent and ascent line is technique that will be put into practice.