How to deploy a SMB (Surface Marker Buoy)

Deploying a Surface Marker Buoy (SMB) from depth is a valuable diving skill. In many diving locations, this safety precaution signals your position to the surface and indicates that you're preparing to ascend. In an area like Nusa Penida, where we experience currents, you will see all dive pros and many other divers carrying an SMB clipped to their gear, as it is a very important safety equipment!

While basic SMB deployment from the surface is taught in your Open Water Course, deploying from depth (called a Delayed SMB or DSMB) requires additional practice but soon becomes second nature.

Tips for Successfully Launching a DSMB

• Give yourself adequate space to prevent line entanglement with other divers

• Ensure your reel and SMB are securely fastened together - a poor clip or loose knot could result in your SMB floating away without you

• In currents, turn your back to the flow and deploy the SMB in front of you to prevent the line from tangling in your equipment

• Slightly deflate your BCD to become negatively buoyant, compensating for the upward pull when the SMB inflates

• Prepare your reel, then use your alternate air source to push a small amount of air into the SMB so it takes shape before fully inflating and releasing it

  
  

The goal is to effectively signal your location to the surface, so ensure the SMB is fully inflated with tension on the line so it stands upright in the water column.

When ascending, gradually reel in the line to keep the SMB directly above you. Upon reaching the surface, maintain the SMB in an upright position if your boat isn't immediately visible.

It's good practice for all divers to carry an SMB and know how to use it properly!