Mixed Gas Diving Is Complex
Diving is a complex pursuit where safety hinges on numerous factors, one of which is the type of breathing gas used. While many assume scuba tanks are filled solely with oxygen, a variety of gas mixtures are utilized to meet different diving needs. Here, we explore the most common and specialized diving gas mixes, each designed for specific underwater conditions and diving requirements.
Standard Air: The Common Choice
The starting point for many divers is standard compressed air, which consists mainly of 21% oxygen and 78% nitrogen, with traces of other gases. This mix is affordable and accessible, but has its limitations. At greater depths, nitrogen can induce nitrogen narcosis, a condition characterized by impaired judgment and euphoria, necessitating other gas options beyond 40 meters to avoid hazards.
Nitrox: Extended Underwater Times
Nitrox comes into play when divers need to prolong their underwater ventures. With increased oxygen levels, typically between 22% to 40%, Nitrox enables longer bottom times by reducing nitrogen absorption. However, increased oxygen levels mean Nitrox divers can’t delve as deep as possible with regular air.
Advanced Mixes: Trimix and Heliox
Technical divers exploring greater depths often turn to Trimix and Heliox, which incorporate helium to mitigate the adverse effects of nitrogen at depth. These gases allow dives beyond recreational limits, making them ideal for excursions surpassing 130 feet. Trimix blends adjust nitrogen and oxygen levels with helium, while Heliox incorporates only helium and oxygen, eliminating nitrogen entirely. Such advanced gas mixtures require precise gas blending and specific training due to their complexity and cost.
Pure Oxygen: For Decompression and Emergencies
While pure oxygen isn’t used for general diving due to its shallow depth toxicity, it plays a critical role in decompression and emergency scenarios. Oxygen’s high reactivity demands special handling and is generally reserved for technical use or surface-level emergency treatments for conditions like decompression sickness.
The Role of Argon in Drysuits
Although argon isn’t suitable for breathing, it provides excellent thermal protection when used to inflate drysuits. This property is crucial for divers in colder environments, enhancing thermal comfort during dives.
Commercial Diving and Gas Supply Considerations
In the commercial diving industry, the choice of gas mixture isn’t just a matter of safety but efficiency. Mixed gases routinely help overcome the limitations of air, permitting prolonged and deeper tasks underwater. Optimizing the primary breathing gas supply is key, ensuring the safety and success of complex underwater operations.
Frequently Asked Questions
What is gas blending?
Gas blending refers to the precise mixing of different gases to create specific diving gases like Nitrox, Trimix, or Heliox, tailored to various diving conditions and objectives.
Why is helium used in diving gases?
Helium is valued for its low narcotic potential compared to nitrogen, allowing divers to maintain clear thinking at great depths and reducing the risk of nitrogen narcosis.
How does a closed circuit rebreather benefit technical diving?
A closed circuit rebreather efficiently recycles the diver’s breathing gas, which drastically extends dive duration and minimizes gas consumption, making it ideal for long technical dives.
Sourcing Custom Mixed Gas For Diving
Last, finding the right mixed gas supplier to meet your requirements can be difficult. It might surprise you to learn that nexAir, known as a supplier for a broad range of industrial gas, also provides custom gas mixes for divers. With retail outlets throughout the Southwest United States, dialing in your requirements for mixed gas diving maybe just a short drive away.
