Home Dive Training Keep Your Buoyancy Under Control

Keep Your Buoyancy Under Control


Ever notice how divers with excellent buoyancy seem to have more fun? Perfecting your buoyancy won’t happen overnight, but with a little practice and refinement of your equipment and weighting, you can be well on your way to gliding effortlessly through better, longer dives. Having good buoyancy increases divers’ overall comfort level, which instills more confidence and allows for better judgement when problem-solving underwater. Having poor buoyancy can lead to some frustrating and uncomfortable situations. It can also lead to some of the most common and the most serious dive injuries. Whether you’re on the surface or deep underwater, staying in control of your buoyancy is vital to your safety.

By Caitlyn Ruskell, DAN Content Writer/Editor

Failing to establish positive buoyancy on the surface has been a contributing factor in too many dive accidents. It’s also one of the more obvious signs of diver panic. If you’re struggling at the surface, get positive: Inflate your BC until you’re floating effortlessly, and ditch your weights if you need to. If you see someone else struggling, tell them to do the same. If you’re properly trained and it is safe to do so, you may need to assist a panicking diver in establishing positive buoyancy.

Inefficient buoyancy control underwater can have various consequences. Ear injuries, the most common injuries reported to DAN, are just one type of injury that results from ineffective buoyancy control. If you feel uncomfortable pressure in your ears or sinuses as you descend, stop your descent, ascend until the pressure resolves, attempt to equalize again and only continue to descend if you can easily equalize. Alternatively, if you experience a reverse block on ascent, you should descend a bit and attempt to equalize. Improper buoyancy control can not only cause these issues but can make troubleshooting them nearly impossible.

In addition to ear injuries, hazardous marine life injuries often result from poor buoyancy control. Most marine-life injuries are due to unintentional contact between a diver and marine organisms. Poor buoyancy control makes this unintentional contact much more likely and may even provoke animals to engage in defensive behavior. Injuries such as coral scrapes, stingray envenomations, jellyfish stings, lionfish stings, and puncture wounds from sea urchin spines can almost always be avoided with good buoyancy control. These injuries can be extremely painful and can expose you to gnarly secondary infections, so you should thank yourself in advance for avoiding them. The animals will thank you too.

Poor buoyancy may not always be the direct cause of injuries in divers, but one of the most common triggers for dive accidents, running out of air, is often facilitated by poor buoyancy. Poor buoyancy control can cause you to descend deeper than planned. If you fail to make adjustments in your dive plan based on an accidental depth increase, you could potentially increase your risk of DCS, and you would definitely increase your gas consumption. Using your power inflator to make constant adjustments to your buoyancy underwater can also dramatically increase your air consumption, and if you do not constantly monitor your air supply, this could contribute to an out-of-air emergency.

When it comes to lack of buoyancy control, the worst-case scenario is an uncontrolled ascent. Uncontrolled ascents put divers at risk for lung overexpansion injuries (pulmonary barotrauma). They also substantially increase the risk for an arterial gas embolism. Fortunately these risks can be mitigated easily.

Buoyancy control begins with knowing your equipment. Before every dive, check to make sure your BC is holding air and properly venting it. Also, ensure that your power inflator is functional and not sticking. Before you ever dive a BC in open water, you should be aware of how it responds when you add or vent small amounts of air. You should also remember and account for the ways other equipment affects your buoyancy on your dives. Exposure suits, especially drysuits, can significantly affect your buoyancy, and their effects can change throughout dives. Like exposure suits, the way your cylinder affects your buoyancy also changes throughout your dive; tanks become more buoyant as you deplete your gas supply. To make sure you have control over your buoyancy it is imperative that you maintain and regularly service your equipment.

Once you’ve made sure that your equipment is fully functional and compatible with the type of diving you plan to do, refine your weighting. The amount of weight you wear should allow you to descend, not make you sink, and you should never wear more weight than your BC can lift. Once you think you’ve chosen the correct amount of weight, do a final buoyancy check at the surface before your dive.

The next step to perfecting your buoyancy is to get in the water and dive, dive, dive. With a little bit of dive experience and some attention to detail, you’ll be set up to avoid a multitude of injuries and accidents. You’ll also be well on your way to your best dives yet.