What You Need to Know About Deploying Surface Marker Buoys

Diving is a hobby that many people enjoy. After all, who doesn’t want to see mesmerising underwater ocean views? The world beneath is full of magnificent sea creatures, with more that divers have yet to discover.

As impressive as it sounds, the unfortunate fact is that diving also poses risks to people who do it. The most common problem is running out of oxygen underwater, which causes decompression sickness. If you resurface too fast or dive for too long, it could put you in grave danger. Because of the potential risks that diving poses, divers are given surface marker buoys (SMBs) that can help keep them safe. 

What are SMBs, anyway? This article will shed some light on the matter. Read on below to learn more.

A Closer Look at SMBs

The SMB, more typically known as the blob, is an inflatable signalling tube that allows people on a water vessel to know the positions of divers.

There are two kinds of SMBs:

  • Standard SMB - A standard SMB is one that a diver tows around for the duration of their dive.
  • Delayed SMB - Delayed SMB is the most used kind, which divers deploy underwater only to signify that they are ascending back to the surface.

SMBs may seem pretty straightforward to use, but that’s far from the truth. In some cases, divers often have difficulty in deploying SMBs. Some of the usual problems involve tangled reels, divers attaching themselves to reels, and being unable to control their buoyancy as they ascend.

For this reason, it’s crucial to know the proper way to use SMBs. These include:

Prepare Early

You can inflate SMBs at the water’s surface, but they’re more effective when deploying the device from underwater. It gives the vessel driver time to get into position to extract divers as soon as they hit the surface. It also signals to other boats that you’re in that position, and they should steer clear of your SMB.

Deploying your SMB early on makes it easier to control your buoyancy, and you also don’t need to get as much air in it.

Observe the Environment

You have to make sure that you’re neutrally buoyant so that your ascent is easier. Additionally, you also need to check if there aren’t any obstructions in the path of your ascension.

Warn Your Diving Partner

You should let your diving partner know every time you’re ascending to the surface. Signal them by saying ‘You, Watch, Me, Shoot,’ and they should respond with ‘Okay.’ You will also be doing your diving partner a favour because you can work with each other for a better ascension, making no room for unwanted incidents.

Using the SMB

Most divers prefer to store their SMBs and reels in a BC pocket. While there’s nothing wrong with that, it’s recommended that you have the reel clipped to a D-ring on the buoyancy compensator in a bungee cord loop so that it won’t go away while underwater. On the other hand, you’ll have to attach the reel line if it’s not already connected to the SMB. All you need to do is to make sure it’s not tangled.

Filling up your SMB depends entirely on the method you’re using. Many SMBs open at the bottom, where you can use your regulator to fill them up. You can do this by removing your occy underneath the SMB, or you can also hold the opening above your head to catch exhaust bubbles. If you’re doing the latter, it’s worth noting that you don’t have to take the primary off your mouth.

Conversely, you can fill SMBs with low-pressure or oral inflators with your BC inflator hose—just remember to put it back on your BC after you’re done.

Ascending to the Surface

Keep a solid grip on the reel, but don’t hold onto the SMB once it begins to ascend because it will be fast. It causes decompression sickness, which is what you should avoid at all costs. If you’re having trouble with staying slow, try adding less air to your SMB or make yourself a little negatively buoyant.

Once you’re in the clear, wrap up the reel, line, and any other SMB component in one hand. Pull them all together to inflate the SMB. When it hits the surface, wind back on the reel’s line and apply extra tension to make it stand up straight.  Again, ascend slowly for safety purposes.

After reaching the surface, continue pulling down on the SMB so that it remains upright until the vessel can pick you up.


As much as possible, try to practice using an SMB in a controlled environment. You could consider doing it in a swimming pool for an immersive experience because what happens there could happen when you’re out during dives. There’s nothing wrong with not getting things right on the first try unless it’s your safety that’s on the line.

Diving is a fun experience, but the enjoyment goes out of the window if people don’t observe safety measures. Swim Secure is a dealer of top-quality marker buoys in Australia that can help make your diving experience more exciting. Contact us today to learn more!