Underwater Dangers III : A Diver’s Guide to Physical Hazards

Underwater Dangers III : A Diver’s Guide to Physical Hazards

Written by Urval Patel, November 2024.

Scuba diving is an exhilarating activity that allows people to explore the hidden wonders of the underwater world. While the focus is often on marine life and the beauty of coral reefs, the physical hazards that divers may encounter are just as critical to understand. These hazards, if unaddressed or underestimated, can lead to accidents or even life-threatening situations. This is the last in a series of articles that looks at marine hazards from venomous creatures, sharp corals and unpredictable behaviour of marine animals in ‘Underwater Dangers: A Diver’s Guide to Marine Life Hazards’, to challenges posed by strong currents and surges in ‘Underwater Dangers II: A Diver’s Guide to Environmental Hazards’, and finally, we will look at underwater structures and debris, barotrauma, and equipment failure. This article provides an introduction to the common physical hazards and potential sources of human errors that divers should be aware of when scuba diving.

1. Barotrauma (Pressure-Related Injuries)

One of the most common physical hazards divers face is barotrauma, which occurs due to changes in pressure as a diver ascends or descends in the water. As you descend, water pressure increases, and as you ascend, it decreases, which can affect air spaces in the body, such as the ears, sinuses, and lungs.

Ear Barotrauma: The most frequent form of barotrauma occurs in the ears when divers fail to equalize the pressure properly. If the Eustachian tube does not open to equalize pressure, the increasing water pressure can cause pain or damage the eardrum, leading to hearing loss or dizziness.

Sinus Barotrauma: Similar to ear barotrauma, sinus barotrauma occurs when air in the sinuses cannot equalize during pressure changes. This results in intense facial pain, nosebleeds, and in severe cases, sinus damage.

Lung Barotrauma: The most serious form occurs if a diver ascends too quickly without exhaling properly, leading to lung over-expansion. This can result in serious injury, such as pneumothorax (collapsed lung) or air embolism, which is life-threatening.

Prevention Tips:

• Equalize pressure early and often during descent by pinching your nose and gently blowing or swallowing. If your ears still hurt, do stop and ascend slightly to equalize again. 
• Ascend slowly and in a controlled manner, never holding your breath.
• Be aware of symptoms such as discomfort, pain, or dizziness, and take action immediately to avoid injury.

2. Decompression Sickness (The Bends)

Decompression sickness, commonly known as “the bends,” occurs when a diver ascends too quickly, causing nitrogen bubbles to form in the body’s tissues and bloodstream. At deeper depths, nitrogen dissolves into the bloodstream due to the increased pressure. If a diver surfaces too fast, the rapid decrease in pressure causes these nitrogen bubbles to expand, potentially blocking blood vessels and causing damage.

Symptoms of decompression sickness include: Joint pain (especially in the arms and legs); dizziness, fatigue, or confusion; numbness, paralysis, or muscle weakness; skin rashes or mottling, and; shortness of breath or chest pain.

Prevention Tips:

• Follow dive tables or a dive computer to track safe ascent rates and ensure proper decompression stops.
• Stay hydrated before and after your dives. This could reduce the risk of decompression sickness.
• Plan dives carefully and avoid flying or traveling to higher altitudes immediately after diving, as this increases the risk.

3. Poor Visibility and Disorientation

Visibility can be affected by various factors such as water turbidity, sediment, plankton blooms, or even night diving. Reduced visibility increases the risk of disorientation, separation from dive buddies, or unintended contact with hazards like rocks, corals, or marine life.

Challenges with poor visibility including; losing sight of your dive group or buddy; difficulty reading dive instruments like gauges or compasses; increased chance of colliding with objects or other divers, and; increased anxiety or panic in some divers.

Prevention Tips:

• Always carry a dive light when diving in low-visibility conditions.
• Practice navigation skills and familiarize yourself with the dive site beforehand.
• Stay close to your dive buddy and communicate frequently to ensure you don’t get separated.

4. Entanglement

Entanglement is another hazard divers may encounter, especially when exploring wrecks, caves, or areas with dense marine vegetation such as kelp forests. Loose fishing lines, nets, or other underwater debris can trap a diver, potentially restricting movement or causing panic.

Prevention Tips:

• Always carry a dive knife or cutting tool to free yourself in case of entanglement. But remember, please don’t panic. 
• Be cautious when entering areas with poor visibility or confined spaces.
• Keep gear streamlined to avoid snagging lines or marine debris.

5. Cold Water and Hypothermia

Diving in cold water presents additional physical hazards, even for divers wearing wetsuits or drysuits. Cold water can lead to rapid heat loss, resulting in hypothermia, a potentially life-threatening condition where the body loses heat faster than it can produce it.

Symptoms of hypothermia include: shivering; numbness in extremities; slurred speech or confusion, and fatigue or dizziness

Prevention Tips:

• Use proper thermal protection, such as wetsuits or drysuits, depending on water temperature.
• Limit exposure to cold water and take breaks between dives to warm up. Have warm drinks to keep warm as well. 
• Stay hydrated and avoid alcohol or caffeine before diving, as they can increase the risk of hypothermia. 

6. Equipment Failure

Properly functioning dive equipment is essential for a safe dive, and equipment failure can turn an otherwise routine dive into an emergency situation. Common equipment failures include malfunctioning regulators, buoyancy control devices (BCDs), or air supply issues.

Prevention Tips:

• Perform thorough pre-dive equipment checks, including regulators, BCDs, and tanks.
• Regularly service dive gear according to manufacturer recommendations.
• Practice emergency procedures like air-sharing or controlled emergency ascents so you’re prepared in case of failure.

Conclusion

While scuba diving offers an unparalleled glimpse into the underwater world, it also comes with various physical hazards that divers must respect and understand. From pressure-related injuries to equipment failures and strong currents, these risks require careful planning and preparation. By being aware of these physical hazards and taking proper precautions, divers can minimize risks and ensure a safe and enjoyable underwater experience.

Now is a great time to take up the Rescue Diver course which would better prepare you to attend to issues that may arise while diving. There are other specialty courses as well that would help improve your diving skills. For more information on this, feel free to WhatsApp or email us at hello@flowdive.center.