Understanding the Fundamentals of Sharing Air
When sharing air from a portable scuba tank, the primary rule is to remain calm and communicate clearly. The act of sharing air, often referred to as an “alternate air source” or “buddy breathing” procedure, is a fundamental safety skill in scuba diving. It’s not about casual sharing for convenience, but a controlled emergency protocol used when one diver is low or out of air. The core etiquette revolves around safety, efficiency, and minimizing stress for both divers. The process should be practiced in a controlled environment, like a swimming pool or confined water, before ever being needed in open water. Panic is the greatest enemy in any diving emergency, and a well-rehearsed air-sharing drill ensures both divers can ascend safely.
The Step-by-Step Protocol for a Safe Air Share
The procedure is methodical. The out-of-air diver must signal their situation clearly, typically by slashing a hand across their throat. The donating diver responds with an “OK” signal to acknowledge the situation and establish control. The donor then offers their secondary regulator (the “octopus”) or their primary regulator (following a specific configuration like the “long hose” setup). The key is for the donor to maintain control of their own portable scuba tank and to make the hand-off while both divers maintain eye contact. Once the regulator is securely with the receiving diver, both divers must hold onto each other, typically by holding each other’s BCD straps or arms. This physical connection prevents separation. The next step is a controlled, slow ascent to the surface, maintaining continuous breathing and never holding your breath. The donor should be the one managing the buoyancy for the pair if possible.
Equipment Considerations and Configurations
Proper equipment setup is not just good practice; it’s a critical part of air-sharing etiquette. The most common and recommended configuration involves an alternate air source, or “octopus.” This is a second second-stage regulator attached to the same first stage on your tank. It should be brightly colored (yellow or red) and secured in the “triangle of life”—the area bounded by your chin and the lower corners of your rib cage—using a quick-release clip. This makes it easy for a stressed buddy to find. Another popular system, especially in technical diving, is the long-hose configuration. Here, the primary regulator is on a 5-to-7-foot hose, which is donated to the out-of-air diver. The donor then switches to their secondary regulator, which is on a shorter hose and worn on a necklace. This setup allows for easier side-by-side swimming during the ascent.
| Equipment Feature | Standard Octopus Setup | Long-Hose Setup |
|---|---|---|
| Primary Regulator | Standard length hose (approx. 28-32 inches) | Long hose (5-7 feet) |
| Secondary Regulator | Octopus, brightly colored, clipped in triangle | Shorter hose (22-26 inches), worn on a necklace |
| What is Donated | The octopus regulator | The primary regulator (long hose) |
| Best For | Recreational diving, simplicity | Technical diving, overhead environments, easier buddy mobility |
Communication: The Non-Verbal Language of Safety
Underwater, your ability to communicate clearly without words is paramount. Etiquette dictates that you and your buddy discuss and agree on hand signals before the dive during the pre-dive briefing. The universal signal for “I am out of air” is a flat hand drawn sharply across the throat. The signal for “I am low on air” is typically a clenched fist tapped against the chest. You must also agree on signals for “How much air do you have?” (pointing to your gauge) and “We need to end the dive/ascend” (a thumb-up gesture). The donating diver’s calm and affirmative “OK” signal after receiving the distress signal is crucial—it reassures the distressed diver that help is coming. Throughout the air-sharing process, maintaining eye contact is a powerful non-verbal tool to keep both divers calm and focused.
Pre-Dive Planning: The Most Important Etiquette Rule
The most critical aspect of air-sharing etiquette happens before you even get wet. A comprehensive pre-dive buddy check (often remembered by the acronym BWRAF—Buoyancy, Weights, Releases, Air, Final OK) is non-negotiable. During this check, you must physically confirm your buddy’s air is on, check their submersible pressure gauge (SPG) to ensure the tank is full, and locate and test their alternate air source. You should also agree on a maximum depth for the dive and a turn-around pressure—the air pressure at which you will begin your ascent. A common rule for recreational divers is to turn the dive when the first diver reaches 100 bar (approx. 1500 psi), ensuring a sufficient reserve. Discussing the air-sharing procedure during the briefing ensures there are no surprises in an emergency.
| BWRAF Step | What to Check | Why It’s Critical for Air Sharing |
|---|---|---|
| Buoyancy | BCD inflator/deflator operation | Ensures a stable, controlled ascent during an air-sharing emergency. |
| Weights | Weight belt or integrated weight system release | Quick-ditch weights are a last-resort buoyancy aid for a rapid, emergency ascent. |
| Releases | All BCD clips and buckles | Ensures you can help your buddy or yourself in a entanglement scenario. |
| Air | Tank valve on, air is flowing, gauge reads full, locate alternate air source | The core of the check. Confirms the air supply is ready and the octopus is accessible. |
| Final OK | Mutual signal that both divers are ready | Confirms that both divers are mentally prepared and have completed the check. |
Managing Air Consumption and Dive Profiles
Good etiquette means being responsible for your own air consumption and not putting your buddy in a position where an air share becomes necessary due to your poor planning. Monitor your SPG frequently—at least every 5-10 minutes. Factors like exertion, depth, cold water, and stress dramatically increase air consumption. A relaxed diver at 10 meters might have a Surface Air Consumption (SAC) rate of 15-20 liters per minute, while a stressed or cold diver at 30 meters could easily consume 40-50 liters per minute. Plan your dive to be the one who ends with more air, not less. This proactive approach is the hallmark of a considerate and skilled diver. If you consistently use air much faster than your buddy, it’s your responsibility to work on your breathing techniques and buoyancy control.
Post-Event Etiquette and Debriefing
If an air-sharing event occurs, even a practice one, etiquette requires a post-dive debrief. Once safely back on the boat or shore, discuss what happened calmly. What was the trigger? How did the signals work? Was the equipment easy to locate and use? Was the ascent controlled? This is not about assigning blame, but about learning and improving for future dives. It reinforces the skills and builds confidence between buddies. Acknowledging that the situation was handled well, or identifying areas for improvement, turns a potentially negative experience into a powerful learning opportunity and strengthens the buddy team for the next dive.