SMB Deployment: How To Successfully Deploy An SMB


A surface marker buoy (SMB) is a crucial part of any diver’s scuba gear and equipment. These big, inflatable tubes made from brightly colored fabric are used to mark a diver’s location and may feature reflective materials to make them more visible and easier to spot. Surface marker buoys are inexpensive, but they are very useful and could potentially save the diver’s life; however, this can only be true if you know how to deploy an SMB properly.

Many divers who have seen their diving guides deploy an SMB tend to think that SMB deployment is a pretty straightforward affair. However, they quickly realize that this isn’t always the case as soon as they give it a try. More often than not, they come across a variety of problems when deploying their SMBs like tangled reels, divers attaching themselves to reels, and divers not being able to control their buoyancy during deployment. All of these can lead to pretty serious ascent rate issues and ultimately increased risk of decompression sickness. Also, although scuba diving is generally safe, there are still reports of divers getting lost or getting involved in serious surface accidents that involve boats or other watercraft. That said, learning how to deploy an SMB correctly is one of the most important skills that divers should learn.

How to Deploy a Surface Marker Buoy

There are several types of surface marker buoys, all of which have their own unique features. However, the majority of these will follow a generalized step-by-step procedure during deployment.

Step 1: Maintain Neutral Buoyancy

Before deploying your SMB, ensure that you are neutrally buoyant and that you have complete control of your buoyancy. Being neutrally buoyant means that you are in a state of balance and are floating in the water without too much effort. If you find yourself rising that means that you are positively buoyant; conversely, if you are sinking then that means that you are negatively buoyant.

To become neutrally buoyant, experts recommend that you prepare for your dive with a so-called compensation trial. Also, if you feel negatively buoyant at the bottom, add one or two small, quick bursts of air to your buoyancy compensator device (BCD). Just remember to let go of the inflator button, otherwise, you may find yourself overinflated and making a runaway ascent. Once you’re neutrally buoyant at that depth you can start preparing to deploy.

Step 2: Take Out Your SMB

Bring out your surface marker buoy, unclip the reel and check that the SMB is attached to the end of the line. If the spool isn’t already attached to the SMB, you’ll have to attach it manually. You can do this by locating the small D-ring located on the bottom, then attach the D-ring to a loop in the line from the spool. Afterward, unreel just a little line to make sure the loop in the line isn’t tangled around the spool.

Step 3: Check that You’re Clear

Before inflating your surface marker buoy, check that your surroundings are clear for deployment. Make sure that your diving buddy and other divers are far away enough from the line to ensure that they don’t get tangled in the line. Also, look up and make sure that your SMB will not come into contact with other objects above you like other divers, swimmers, and boats.

Step 4: Inflate Your Surface Marker Buoy


Once you’re cleared to deploy, wrap up the spool, line, and any excess SMB material into one hand. Check again to make sure that no materials like the line are wrapped around your fingers or dive gear and the reel is unlocked. Now, holding SMB and spool with one hand, inflate the SMB till about half full using your octopus or alternate air source. Once the SMB is half full, check that the line attachment is in place, and keeping your hands clear of the spinning reel, inflate the buoy slowly with the correct amount of air.

Filling up your SMB generally depends on the type of surface marker buoy that you have. With some SMBs, can vent air from your regulator to fill them up, you can do this either by purging your octopus underneath the SMB or holding the opening above your head to catch your exhaust bubbles. Some divers even have a secondary inflator hose attached to their scuba regulators for this purpose. In any case, it is important to practice how to inflate your SMB well beforehand.

Step 5: Deploy

Once your surface marker buoy is inflated, let it rise to the surface. Keep a solid hold on the reel, but don’t hold onto the line or SMB after it begins to ascend or you may be pulled up with it. If you have trouble staying down, try making yourself slightly negatively buoyant.

Step 6: Straighten Your Surface Marker Buoy

Once you see the buoy hit the surface of the water, the wind backs the line on the finger spool and apply some extra tension on the line to make your surface marker buoy stand straight up.

Step 7: Ascend

Start your ascent to the surface while reeling in the line. Remember to keep the line taut throughout your ascent because a slack in the line can cause your SMB to fall to the side and allow air to escape. Also, ascend at a safe rate, and don’t forget to check your dive computer and stop for your safety stop.

Step 8: Keep the SMB Upright

Once you reach the surface, you still need to keep your SMB upright so that it stands above the water and remains visible until the boat comes to pick you up. To do this, simply continue pulling down on the lower end of the surface marker buoy.

Globo Surf Overview

The aquatic world is filled with much interesting marine flora and fauna and fascinating landscapes. However, as beautiful as it is, this environment can also pose some threats to divers, some of which may put them at serious risk of harm and injury, or worse, death. Thus, divers must always make sure that they err on the safe side of diving, and this means carrying and knowing how to deploy an SMB correctly. SMB deployment may pose some challenges at first, but it is a skill that can be learned with enough practice until it eventually becomes second nature for the diver.

More Scuba Reviews:


  1. The Secret Sauce for Surface Marker Buoy (SMB) Deployment, TDI-SDI
Globo Surf
My name is David Hamburg. I am an avid water sports fan who enjoys paddle boarding, surfing, scuba diving, and kite surfing. Anything with a board or chance I can get in the water I love! I am such a big fan I decided to start this website to review all my favorite products and some others. Hope you enjoy!