Most experienced divers have used surface marker buoys; less experienced divers have very likely seen them in use at some point. These simple devices have a number of uses that can make scuba diving safer and easier. Here, we’ll take a closer look at the humble surface marker buoy, with an eye toward informing newer divers about the many ways in which they can be put to use.
Without a SMB…
Without a surface marker buoy (SMB), the following scenario might be a scary reality: Imagine that you’re diving at your favorite reef site. Conditions were ideal when you made your descent, but a storm kicks up, complete with rain, wind, and some accompanying current. When the light from above decreases and the currents start to increase, you realize that it is time for you and your buddy to get to the surface.
You make a difficult ascent, and your safety stop is no picnic. When you break the surface, the two of you look around for the dive boat and see it more than 200 yards away. The swells are getting larger, and the boat bobs in and out of view. You know that the crew is watching for you, but at the same time, you know that the odds of being seen in this weather are slim.
After a long surface swim, you are spotted a mere 25 yards from the boat. Once aboard, you and your buddy collapse into an exhausted heap.
SMB Basics
A surface marker buoy is a brightly colored floatable device that indicates a diver’s general position. All SMBs are connected to their users via a reel, which ensures that the diver is basically right below the buoy.
Depending on circumstances and previously arranged codes within a given group of divers and/or a boat crew, surface marker buoys can be deployed to mean a variety of things. It is important to discuss usage or potential usage of SMBs as part of dive planning, particularly since there is no universal standard for using them in various situations.
There are several different sizes, brands, and types of surface marker buoys available; however, there are some very simple distinctions which can be made among these.
-
Open-ended surface marker buoys are very simple tubes with one open end that remains underwater to prevent the air inside from escaping. This type of SMB is best for diving in calm conditions.
-
Closed-end surface marker buoys are also simple tubes, however they are better for use in choppy water or in situations where choppiness or other water movement could occur which could cause an open-ended SMB to deflate. These buoys have inlet valves and pressure control outlet valves that ensure they remain inflated and easy to spot.
-
Delayed surface marker buoys are deployed from underwater when necessary. This ensures that divers do not have to worry about their SMB lines becoming entangled, yet it allows for all the benefits surface marker buoys provide. A delayed SMB fits easily into a pocket and can be rapidly inflated when necessary. Once inflated, the surface marker buoy ascends quickly to the surface, marking the position of the diver for easy response.
How to Use a Surface Marker Buoy
Exact instructions for using your surface marker buoy will vary depending upon the type of buoy you purchase. Be sure to review these instructions before diving with a new SMB.
Use care when utilizing a surface marker buoy, since the line that connects you to it can easily become entangled with your own gear, with items at dive sites, and with other divers’ lines. In some cases, the reel can become stuck and fail to unwind properly. Practicing with your SMB will help you to familiarize yourself with it; be sure to do this in shallow water with a reliable buddy.
When to Use a Surface Marker Buoy
There are many different scenarios that call for the use of a surface marker buoy. Some of the most common are outlined below:
-
As an aid to ascent. When currents, particularly down currents, are strong, it can be very helpful to use your surface marker buoy to aid in a safe, controlled ascent.
-
As a means to prevent disorientation. If you are diving in a fairly featureless area, it can be easy to start feeling disoriented and wonder if you are somehow drifting away. Using a SMB can provide you with some peace of mind and an easy connection to the surface.
-
To indicate that an emergency is occurring. One of the reasons you should always carry a delayed surface marker buoy (or two in different colors) is to indicate that an emergency is occurring. Deploying a SMB in the event of an emergency alerts people at the surface to prepare themselves to help. In many cases, a buoy in one color can be made to mean one thing, while a buoy in another color can be made to indicate another thing.
-
To indicate that you are ready to be picked up after drift diving. Drift diving is fun, but doing it without a surface marker buoy can be extremely risky. Once you reach the end of your dive, deploying your SMB shows the boat captain that you’re ready to be picked up, plus it makes you much easier to spot.
-
To mark your position if you are lost. A surface marker buoy sits several feet above the waterline, and is easy to see from a distance. In the event you are lost or separated from your group, you can deploy a surface marker buoy to increase your odds of being safely rescued. In bad weather or at night, a strobe attached to the top of the SMB makes you even easier to spot.
-
To indicate your presence in shared areas. In areas where boats, surfers, fishermen, and others are present, a surface marker buoy shows your position and prevents accidents.
These inexpensive devices can save your life, and they can make life easier, too. Be sure to mark your surface marker buoys with your name, address, and other emergency contact information. If you are diving in an area where English is not commonly used, be sure to include your details in the language used locally. Finally, ensure that you inspect your SMBs regularly and replace them if needed.