Minimising Rebreather Fatalities
By Stuart Ford
Unfortunately in our sport there are accidents and fatalities, as the founder of Rebreather World I often get to hear about details that for one reason or another do not get made public. The purpose of this article is to share the output of some work I have being doing for a number of months on how we can make our sport safer and minimise the risk of a fatal accident for us as individuals.
You will note I say minimise, that is because that I believe that life itself is hazardous, even more so when we do something unnatural like breathing underwater where we depend on a mechanical device to support life. If that device ceases to function and we do not act appropriately then a fatality will occur.
We can minimise that possibility by following some easy rules:
1 Never ever dive when there is something wrong with your unit. It does not matter what that fault is, it will start you down the incident pit. If it is not working 100% then do not start the dive call it before you get wet.
2 Set your equipment up consistently (fresh sorb every deep dive!) I believe the only way to do this is to follow a written checklist that you sign off every time (In my opinion it is too easy to click through electronic checklists). We have all heard of people who died without switching their unit / O2 on wouldnt have happened if they had a checklist they followed religiously. Consider laminating your checklist for a final run through before you jump in.
3 Know of any little foibles or funnies that affect your unit. Make sure that you have taken any precautions to minimise the possibility of these occurring or to ensure that you can recognise them if they occur. I would suggest speaking to fellow divers, your instructor and searching our forums to identify them.
4 Test your cells before / at the start of every dive and ensure they can read at least 20% higher than the PPO2 you intent to use to complete the dive (gives you a safety margin). You can do this in a number of ways:
- A pressure pot you can put your units head in.
- The device Ron Micjan makes to test cells
- Or my favourite combine it into your bubble check at 6m. At 6m I stop we inspect each other and I do an O2 flush and make sure my cells all get over 1.55ish and I then I can continue my dive on my usual 1.2 1.3 ppo2 and feel fairly happy.
5 Carry bailout and know how to use it / practise regularly. I am not going to go into a debate on what bailout is best for you, just have enough to get up. If you dont have bailout and something goes wrong (Murphey anyone) you will die.
6 If something goes wrong on the dive with your Rebreather, it does not matter what it is, bailout and call the dive. Do not try and go back on the loop do not try and continue the dive bail out, surface and live to dive another day.
There are multiple options for staying on the loop, but they all carry additional risk compared to bailing out . You may well advocate following any of these options but the point I make is that the safest possibly option is to bailout to a completely redundant and independent system.
Take note of this
do not ever head for the surface if something goes wrong. You bailout out then you ascend.
7 Dive in a buddy pair and stay together! If one person calls the dive you both call the dive. If somebody has an issue you need to be near enough to help them straight away. This I am sure will be contentious but in my research I have found over 5 incidents where people survived as their buddy brought them up, several where people died as there was no buddy pair (grey area) or the buddy pair split up and only one where it is strongly suspected that both people died as a result of one buddy getting into difficulties and causing the death of both of them.
This is an individual choice and I would urge you to discuss it with your buddy and your family but I strongly believe that diving in a buddy pair significantly decreases the chances of being involved in a fatal incident.
8 Ensure that you have more than one source of buoyancy. If you run your wing from your dil ensure that you dry suit or an alternate source of buoyancy is provided by a stage. Ensure that you have a set routine that you can VERY quickly ensure positive buoyancy at the surface via either your wing, alternate buoyancy source or dumping your weights, practise this skill and ensure your buddy can do this for you to.
9 Ensure that your kit configuration remains consistent in how it attaches to your body and that both you and your buddy can quickly dekit you if needed.
10 Fly your unit manually using the electronics as a safety net. I strongly believe that anything man made is not perfect we can spend billions on developing electronics be they for space ships, airplanes, rockets or nuclear power stations and we all know they go wrong and cause fatalities a fraction of development cash is spent on Rebreathers compared to the above so lets use them as a safety net.
I was unable to identify a single fatality that occurred when a unit was being flown manually.
The list of 10 above is not designed to be an exhaustive list of how to dive your Rebreather safely nor does it guarantee to keep you alive, however they are the top 10 lessons I believe can be learnt from my recent work of examining fatalities on Rebreathers.
Panic
I feel I also need to spend a moment talking about Panic it kills.
At the most basic level if your rebreather ceases to function and you panic and do not bail out you die. Where as if you do not panic and you bail out you live.
I need to live, this means I must not panic, to help me achieve this I practise my survival skills and envisage how I would deal with panic inducing scenarios.
I have 3 scenarios I think about, practise where I can and visualise how I would deal with them to hopefully stop panic.
Scenario 1 Something wrong with my kit. I bailout to my stage via open loop if possible. I signal my buddy if they have not noticed (I am sure they would have) and we ascend staying in very close contact.
Scenario 2 My buddy goes unconscious I quickly try and identify if they are breathing, that will control how quickly we get to the surface, drowning usually kills people, being bent does not.
Scenario 3 I get lost / trapped Here I stop for a number of minutes I tell myself I have hours and hours to get out / resolve my problem then I plan how I am going to do it and never ever ever give up, I keep fighting and working till I am out and safe.
Those scenarios work for me they might not be the ones for you I would encourage you to work out what your scenarios are and how you can visualise how you would deal with them to ensure you do not panic and you survive.
I hope that this article has been useful to you and will help ensure that you do not become a statistic, it is not designed to be the definitive guide and I am sure that many other Rebreather World members will be able to contribute on how we as individuals can dive safer.
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