No more air
What is the best way to prepare divers for this?
Suddenly running out of air – that’s probably the biggest horror scenario in diving.
That’s why, right from the Open Water Diver course, you practice how to get air from your buddy, how to do a swimming emergency ascent, and how to drop your weights in the process.
But are these martial emergency ascents still relevant today? What should we focus on when it comes to emergency ascents?
Long before the emergency ascent: Gas planning
A real emergency ascent doesn’t start underwater – it starts much earlier.
If you plan your gas reserves, monitor them, and respect the reserve, you won’t even get into the situation of “running out of air.”
Even in the Open Water Diver course, it becomes clear that you have to maintain control over your own air supply. Often, this is done with just a few rules of thumb, such as “be at the safety stop with 70 bar,” but that’s enough for this type of dive. In the advanced courses, a little gas planning is gradually added, which can become increasingly complex.
If you want to know more about gas planning, you can read about it on our dive planning page.
Why you run out of air
The specter of “suddenly running out of air” accompanies all discussions about emergency ascents. But: Why is it that someone suddenly runs out of air?
Technical faults in regulators are extremely rare, and most technical defects lead to a regulator that is free-flowing. Dirt in the tank is conceivable as a cause if it can clog the first stage. Otherwise, there is little technically conceivable. And of course, a submersible pressure gauge can display too much or jam – which you can definitely notice.
So what it usually comes down to is: Not looking at the submersible pressure gauge. It’s that simple.
And that’s why it’s much more important than any emergency ascent to train everyone to know exactly how much air they have left in the tank to within 10 bar. That, and gas planning appropriate to the dive, make emergency ascents largely superfluous.
First choice: The buddy’s octopus – Air Sharing
If a diver runs out of air, the Air Sharing Ascent (ASA) is the first choice – sharing the air supply with the buddy.
It is the only emergency ascent that really works as a controlled, joint solution.
There are several variations here: You can hand over your own regulator or the octopus. And both exist in different configurations.
In the most common typical rec configuration worldwide, the octopus is carried on a slightly longer hose – so that you can easily hand it over without getting in each other’s way.
In the “Tec-Style,” on the other hand, the diver carries the main regulator on a long hose and hands it over when needed. The alternative air supply hangs on a short hose under the chin, usually fixed with a rubber ring.
The principle: The person who has run out of air always gets the functioning source from the buddy’s mouth – i.e., the one that is guaranteed to be breathable. And the long hose guarantees freedom of movement, which you need in technical diving when you can’t go directly to the surface.
And then there are other variants, such as an octopus integrated into the inflator – here, too, the regulator must be handed over from your own mouth.
Some associations prescribe a certain equipment configuration to their diving instructors, and then consistently train the method that goes with it. With SSI, the diving instructor can choose which variant makes the most sense. Only in professional training must the variant with the handover of one’s own main regulator be practiced. The reasoning: This is the version that works in all equipment configurations. Definitely a good argument.
Nevertheless, in beginner training, the best method is always the one that fits your own equipment configuration.
ESA – “just swim up” is not an option!
The Emergency Swimming Ascent (ESA) – i.e., the controlled swimming emergency ascent – is the supreme discipline among the skills in instructor training. But how relevant is it for OWD training, and do we really need it in real diving situations?
The idea is clear: You suddenly realize that you have no more air, the buddy is not there or does not perceive you, so you swim up in a controlled manner. You continuously exhale slowly so that the expanding air can leave the lungs.
When you train this ascent, you notice how long you can exhale continuously – Thanks, Boyle! – and you ideally learn to estimate the speed at which you can make it to the top.
But, honestly: How much has to go wrong for you to get into this situation? You haven’t paid attention to your own air supply, and then you’ve also lost your buddy… Good to know that you still have a chance despite these massive mistakes, but the focus should really be on never getting into this situation.
For training, this means:
don’t abolish it, but classify it didactically. The ESA is not a solution that you train to really need it – but to understand what you better avoid.
At SSI, this exercise is optional in open water. To avoid the risks that a too rapid ascent brings, I think it is a good decision to practice the emergency ascent rather shallow and slow.
Dropping weights, yes, but the EBA? Well…
The Emergency Buoyant Ascent (EBA) – i.e., dropping the weights and ascending with positive buoyancy – is a relic from another time.
It comes from a phase in which one wanted to teach divers to “somehow get up” in case of doubt.
Today we know: The loss of control over the ascent rate is one of the greatest risks for decompression accidents and lung overexpansion.
If we still practice it, then only in the shallows, as shallow as possible – in training, you really don’t have to risk a too rapid ascent.
Talk about EBA: Yes!
Remember that the weights have to go away when you are up – but have a different plan B in case you run out of air down there.
That doesn’t mean you should never talk about the EBA – on the contrary.
It is an important discussion tool to show how much diving didactics have changed: from “survival training” to preventive thinking.
Do you have to turn off the tank to practice?
Never, really never, is the tank turned off to practice an emergency ascent! No association allows that, nobody thinks that’s smart, and if anyone still does that: Stop it, please!
But of course you should also turn off the tank for the student in the OWD course – and in many other courses again. But this does not happen when you then also ascend, but in an extremely controlled situation. You indicate that you are about to turn off the tank, and as an instructor you are directly with the student, can hand over your own regulator at any time. It’s about feeling what it’s like when the air is harder to breathe – to recognize this feeling early and be able to react in time.
With an empty tank, the moment when you get air harder and harder is much longer than with a closed valve – so you have to pay close attention to feel this short moment. For that, you should really not have to concentrate on anything else and feel safe.
But when do you do that in the course? In the SSI skills, this actually belongs before the EBA – the most stupid place imaginable. I like to do that before we practice air sharing for the first time – that’s a good way to explain why you actually practice that.
Conclusion
Emergency ascents are not a training goal – they are a didactic tool to teach responsibility.
Not how to react at the last moment, but how to avoid getting into this situation at all.
Anyone who has understood this teaches differently: calmer, more reflected, with a focus on gas management, buddy communication and forward-looking thinking.
Because the best emergency ascent is the one that nobody needs.
