You're on a relaxing dive enjoying the beauty of the underwater world. You’ve left all your frustration and responsibilities above the surface. After all, this is where you come to “get away from it all,” right??
How will you deal with this scenario? Is the way you’ll handle it optimal? Can you go through the motions in your mind’s eye right now and feel confident you are ready to handle an exasperated out-of-air diver?
When it comes to sharing air, there are many different configurations that divers use.
If you’ve ever wondered why different divers configure their primary regulator and their octopus different ways, and what the pros and cons are of each configuration, you’re going to want to read on because in this article we are going to touch on exactly that!
Disclaimer: Before beginning our discussion on air sharing techniques and configurations, it’s important to note that air sharing, especially in an emergency, is a skill that must be mastered in confined water under the supervision of a qualified SCUBA instructor. Do NOT SWITCH YOUR CURRENT CONFIGURATION without proper training and coaching from a qualified SCUBA instructor!
The origins of air sharing
When SCUBA diving was still new and considered by some to be an “extreme” sport, the gear that was used wasn’t nearly as advanced as it is today.
Early SCUBA rigs only had one primary regulator to breathe from. If your buddy ran out of air underwater, the only option was to share your only regulator by passing it back and forth between you and your buddy. Essentially, you’d take turns taking breaths from a single regulator.
As SCUBA equipment became more advanced a redundant second stage was added. This redundant second stage, which is commonly known as an octopus, could be given to an out-of-air diver independently. Now both the out-of-air diver and the diver donating the air supply could breathe simultaneously from the same tank.
With the ability to have 2 divers breathing from the same tank come many questions about how to best configure your gear. The first question being….
Which regulator should you give a diver in distress?
Before we can address the issue of how to configure your regulators, we need to discuss the major philosophical difference in opinion that many SCUBA instructors have.
While there is not “right” answer here, let’s take a look at some of the pros and cons of each method.
Some of the pros of donating the primary regulator (the regulator the diver is breathing from) include:
- The shared regulator is usually the higher performing regulator: The out of air diver is likely to have a higher breathing rate because of the nervousness / anxiety cause from being out of air.
- It puts the diver that is donating the air source in control of the situation: This means that the diver who is less likely to be in a panicked state becomes the dive leader.
- Because the regulator being shared is the one the diver is breathing from, it needs to be on a longer hose: This allows for the octopus to be on a shorter hose and reduces the chances of it dangling along and getting caught on the reef.
- This configuration is usually more streamlined.
- If an out-of-air and panicked diver rips the functioning regulator out of your mouth, you can instinctively reach for your alternate regulator which is what you would breathe from under this scenario anyway.
The cons of donating the primary regulator in a buddy-breathing scenario include:
- It requires more skill / training to share air in this manner then using an octopus for a distressed out-of-air buddy.
- When using an air2 or other similar regulator that serves the dual purpose of an inflator and a secondary regulator, that secondary regulator may not be as high performing as the primary.
- Because the out-of-air diver needs the diver donating the air to participate, it is more difficult to simply grab an octopus and begin breathing without the assistance of the diver with air: This will make it more difficult for the distressed diver to get to his or her much needed air.
Diving with an octopus to give out as the alternate air source is probably the most common configuration.
The pros of giving out the octopus to an out-of-air buddy include:
- Because the donating diver does not need to actively give up his or her regulator, the person who is out of air can gain access to the gas without having to rely on the donating diver’s skill level or proficiency.
- The diver that is donating the gas never has to take the regulator they are breathing from out of their mouth.
The cons of giving out the octopus to out-of-air buddy include:
- Because the octopus is on a longer hose and is rarely used, it is more likely to dangle or get caught up on a reef or a wreck.
- Because it can dangle behind a diver, if a leak or free flow occurs at the 2nd stage it can go unnoticed for far longer than it would with other configurations.
- Many of the octopus regulators on the market are meant to be cheaper and thus have more breathing resistance. Giving a diver who may already be panicked because they ran out of air a poor performing regulator may aggregate their panic.
Now that we understand some of the pros and cons of using an octopus for an out-of-air diver vs. giving them the regulator you are already breathing from, let’s look at some of the different configurations.
Configurations where you give out the octopus to an out of air diver
The placement of the octopus holder should be somewhere in the “safety triangle”. This is an imaginary triangle that goes from your chin to your waist in front where the octopus can be easily accessed by both the diver and their buddy.
Having the Octopus on a holder
There are many different types of octo holders on the market. Each design has their benefits and drawbacks. The basic premise behind all octo-holders is the same.
They must hold the octopus securely throughout the dive so that the regulator does not accidentally become dislodged and begin to dangle. They must also simultaneously be easy to deploy and come lose if it is needed for an emergency. (IMAGE of Octo holder)
Because of this dichotomy, many octo-holders fail and end up having a diver dangle their octo behind them damaging both the regulator and the reef.
BCD with integrated Octo-holder
Using a D-ring as an octo holder
Yet another creative way to solve the octopus dilemma is to curl it into the D-ring of a BCD.
While this solution is less likely to result in the regulator becoming loose and dangling behind the diver, it does take a bit of getting used to.
Also, it may seem awkward to have the curled-up hose dangling below the D-ring where the octopus is stowed.
Configurations where the primary air source is donated
Air 2 (Regulator Low-Pressure Inflator Combo)
One of the most common configurations where the primary air source is placed on a longer hose and donated is when a diver is using an Air2 or similar inflator / regulator combo.
There are several low-pressure inflator / regulator combos on the market, but the SCUBA Pro Air 2 was one of the first systems that gained widespread use.
By combining the low-pressure inflator and the alternate air source into one, the diver effectively eliminates one hose from their SCUBA rig.
You also eliminate the possibility of having the octopus dangle because the hose used for the low-pressure inflator is typically much shorter than that of an octopus.
As mentioned before, the downside is that it requires the diver to be more involved in an out-of-air scenario because the must give out their primary regulator.
Because the hose on the Air2 is short, it makes it very awkward and less than ideal to be donated to another diver for air sharing.
Hogarthian set up (long hose tech diving set up)
The final configuration worth mentioning is one that was born in cave / technical diving but has been adopted by many recreational divers.
It is known as the Hogarthian rig named after Bill Hogarth Main.
The rig consists of the primary regulator being a longer hose (up to 7 ft) curled around the diver’s body. The octopus is worn on a necklace right under the diver’s neck.
In this configuration the octopus never comes off the necklace. In an emergency, the diver donates the longer hose and then switches to the octo.
Some advantages to this system include:
- Most divers using this configuration opt to have 2 high performing regulators on your rig which eliminates the low performing octopus other divers use..
- It eliminates the possibility of a regulator ever dangling because it’s nearly impossible for the octopus to come loose from the necklace..
- If a diver ever approaches you in an out of air scenario, you can give away your primary and have almost instant access to your back up.
- Because this set up often uses a much longer hose, it will give you the freedom to have some more space to move should you ever have to share air.
The only real downside to this configuration is that it does require training and practice in sharing air using this configuration. Also, if using a long hose for the primary, it does require extra care to not drag the primary regulator on the floor since it is on a very long hose.
Below is a Video where we discuss Air Sharing in Different SCUBA Configurations:
What configuration do you use and why? let us know in the comments below.