The Hidden Dangers of Free Diving to 10 Metres - Freediving is an exhilarating and rewarding sport, allowing you to explore the underwater world in a way that scuba diving simply cannot match. The rush of diving deep with a single breath, the peaceful tranquillity of the depths, and the deep connection with nature are all part of the allure that draws more and more people to take up freediving each year.
However, as with any extreme sport, freediving does come with its risks. Diving to depths of just 10 metres may seem relatively shallow, but even at these modest depths, there are several hidden dangers that freedivers must be aware of and take precautions against. In this blog post, we'll explore some of the key risks of freediving to 10 metres and provide tips on how to stay safe.
Shallow Water Blackout
One of the most serious dangers of freediving, even at shallow depths, is the risk of shallow water blackout. This occurs when the brain is deprived of oxygen, causing the diver to lose consciousness.
The human body is finely tuned to maintain a careful balance of oxygen and carbon dioxide in the bloodstream. When we hold our breath - the oxygen levels drop and the carbon dioxide levels rise. The brain is exquisitely sensitive to these changes, and it will trigger the urge to breathe when CO2 levels get too high.
However, during the ascent from a deep freedive, the opposite can happen - the oxygen levels actually increase faster than the CO2 is expelled. This can "trick" the brain into thinking there is still plenty of oxygen, even as the brain is being starved. The diver may feel no urgent need to breathe until it's too late, and they lose consciousness.
Shallow water blackouts can occur at depths as shallow as 5 or 6 metres and are a major cause of freediving fatalities. The risk is especially high for new or inexperienced freedivers, who may not yet be fully attuned to their body's signals.
To help prevent shallow water blackouts, freedivers should:
- Never freedive alone - always have a safety buddy or surface support
- Use proper breathing and relaxation techniques to extend time underwater
- Monitor their CO2 levels and be attuned to the urge to breathe
- Avoid hyperventilating before a dive, which can further disrupt the body's CO2/O2 balance
- Gradually increase the depth and duration of dives over time
Ear and Sinus Damage
As you descend underwater, the increasing water pressure causes air spaces in the body, like the ears and sinuses, to compress. This is known as equalization, a critical skill for freedivers to master.
If a free diver is unable to properly equalize the pressure in their ears and sinuses, it can lead to painful barotrauma - damage caused by the pressure difference. This can range from mild, temporary discomfort to serious injuries, like ruptured eardrums or sinus infections.
At depths of just 10 metres, the pressure increase is relatively modest - around 1 atmosphere (atm) of additional pressure. But even this small increase can be enough to cause issues for freedivers who struggle with equalization.
Freedivers should practice equalization techniques like the Frenzel maneuver long before attempting any deep dives. It's also important to listen to your body and abort a dive if you feel any pain or discomfort in your ears or sinuses. Pushing through can lead to long-term damage.
Nitrogen Narcosis
Nitrogen narcosis, also known as "rapture of the deep", is another risk that freedivers need to be aware of, even at relatively shallow depths. As you descend underwater, the increasing pressure causes the inert nitrogen gas in your body to have a narcotic, anesthetic-like effect on the brain.
The symptoms of nitrogen narcosis can include confusion, disorientation, impaired judgment, and even hallucinations. At depths of 10 metres, the effects are usually mild, but they can still be dangerous for freedivers who need to make critical decisions about their safety and that of their dive buddy.
To mitigate the risks of nitrogen narcosis, freedivers should:
- Familiarize themselves with the early signs and symptoms
- Dive within their personal depth limits
- Avoid rapid descents that can exacerbate the effects
- Monitor their mental state and be ready to abort the dive if needed
Decompression Sickness
Decompression sickness, or the "bends", is a condition that can occur when dissolved gases in the body form bubbles as a diver ascends too quickly. It can lead to a range of painful and potentially life-threatening symptoms.
While decompression sickness is generally associated with deeper, longer scuba dives, it can still be a risk for freedivers, even at relatively shallow depths. The key factor is the rate of ascent - freedivers who surface too rapidly from a deep dive may not give their bodies enough time to properly off-gas the excess nitrogen.
At 10 metres depth, the risk of decompression sickness is relatively low, but it's still something that freedivers need to be aware of. Appropriate safety stops during the ascent, as well as gradual depth progressions, can help minimize this risk.
Environmental Hazards
In addition to the physiological risks, freedivers at 10 metres depth also need to be mindful of environmental hazards that can pose dangers, such as:
Entanglement Risks: Freediving often takes place in areas with kelp, fishing lines, or other underwater obstacles in which a diver could become entangled in. This can prevent a safe, timely ascent.
Marine Life Encounters: While encounters with sharks or other large marine predators are extremely rare, freedivers may come across venomous creatures like stonefish or blue-ringed octopus that could pose a serious threat.
Cold Water Exposure: Even in warm tropical waters, the temperature can drop significantly at 10 metres depth. Prolonged exposure can lead to hypothermia and impaired physical and mental functioning.
To address these environmental risks, freedivers should:
- Carefully survey the dive site for potential hazards before entering the water
- Wear appropriate thermal protection for the water temperature
- Maintain proximity to their dive buddy or surface support
- Avoid touching or handling any unfamiliar marine life
Importance of Training and Experience
While the risks of freediving to 10 metres may seem daunting, the good news is that with proper training and experience, many of these dangers can be effectively mitigated. Experienced, well-trained freedivers are far less likely to experience issues like shallow water blackout or barotrauma.
That's why it's so important for anyone interested in taking up freediving to seek out professional instruction from qualified, experienced trainers. At Rusty Freediving, our SSI-certified freediving courses cover all the essential skills and safety protocols to ensure our students can dive with confidence.
From breathing techniques to equalization training, our beginner-friendly Level 1 course provides a solid foundation for novice freedivers. And as you progress through the deeper Level 2 and Level 3 courses, you'll continue to build the knowledge and practical experience needed to safely explore greater depths.
Freediving is a truly remarkable sport that allows you to connect with the underwater world in a way that few other activities can match. But it's also a sport that demands respect and a deep understanding of the risks involved. By prioritizing proper training and safety protocols, freedivers of all skill levels can maximize the thrill and minimise the dangers of this captivating pursuit.