Can Pure Oxygen Kill You While Scuba Diving?

The short answer is: yes, but it takes quite a bit of depth and pressure. Pure oxygen can become toxic at depths of 7 meters underwater, causing severe CNS and pulmonary toxicity. Understanding this danger is crucial, especially for recreational and technical divers.

The Dangers of Oxygen Toxicity

While oxygen is essential for life, it can become dangerously toxic, particularly under high pressure. Oxygen toxicity is a significant risk in scuba diving, particularly with pure oxygen. Below 7 meters, oxygen can start to show toxicity signs, and by 15 meters, divers are at risk of seizures due to oxygen toxicity. Dive instructors emphasize the importance of oxygen analysis for every cylinder to ensure safety.

Oxygen toxicity is managed in scuba courses for Nitrox divers, a gas blend enriched with oxygen. The most popular blend for recreational divers is 32% oxygen, compared to 21% in ordinary air. Using pure oxygen can be lethal, as it becomes toxic at a partial pressure of about 1.6 atmospheres, which occurs at a depth of 40 meters. Most divers set their computers to alarm at 1.4 atmospheres and avoid going below 90 feet to avoid the risk of unconsciousness and drowning.

Understanding Oxygen Toxicity

When diving with pure oxygen, the pressure reaches 2 atmospheres at just 10 meters. The increased partial pressure of oxygen can cause central nervous system (CNS) and pulmonary toxicity. While this risk is manageable with proper planning and equipment, it is crucial to recognize what happens when oxygen levels rise too high.

For a detailed explanation of increased partial pressures and their effects on humans, you can refer to the following resources:

UpToDate: Enhancing Understanding of Carbon Dioxide Manifestations Diving Technique: Oxygen Toxicity - How Does It Occur?

Key Takeaways

Remember, while oxygen is essential for life, it becomes toxic under high pressure. Pure oxygen is only used at the surface, and divers must avoid it below 33 feet (10 meters) due to the increased risk of oxygen toxicity. Always use proper equipment, adhere to safety guidelines, and familiarize yourself with the risks associated with diving to ensure a safe and enjoyable experience.

By understanding and respecting the dangers of oxygen toxicity, divers can enjoy their underwater adventures without compromising their safety.