Alternative Source Configuration
Octopus Alternate Source Configuration - taking it for granted
I think it's fair to say that we are all aware of the basic principle that we are unable to breathe underwater without help. When first learning to scuba dive, all training agencies introduce the alternate source, as a backup should our primary source of gas failure. When I learned to dive the kit I trained with had the octopus set up so that it came over my right shoulder, the same as the main reg. Naturally as a beginner I looked to the instructors for guidance and copied this set up. It gave me confidence because I had 2 regulators set up ready for me to use. Maybe we all need to question how we configure our octopus, the real situations when we may need to use it and how we can make it user friendly in a stressful emergency? Sophie Dyhouse NDC Communications OfficerWhat I didn’t think about initially, was that the more likely scenarios for me needing an octopus - running out of gas or first stage failure, which would render my alternate source useless to me. Realising the octopus is more likely to be used by my buddy I moved it to my left side making it easier for them to breathe off, made it highly visible (bright green hose wrap) and easily accessible.
Choice of configuration
‘Safe Diving’ has the following on divers carrying an Alternative Gas Source.
BSAC strongly recommends that all divers carry an Alternate (gas) Source (AS) in the event that they may need to share gas underwater.
It goes on to suggest alternative considerations for a suitable choice of equipment and this has been covered in a previous ‘Safety Talk’. The important consideration in addition to the ‘type’ of Alternate Source is to consider whether it is intended to be used primarily to assist your buddy, as a bailout for yourself, or a combination of both. Whatever the decision it is essential that it is configured and accessible for the intended use.
Positioning
As Sophie indicates above there are different options for configuring the simplest option of a main regulator and octopus rig. The considerations relating to this were actually extensively covered in an NDC Bulletin as far back as 1997 and this analysis is equally as valid today. A copy of the original article can be found at www.bsac.com/NDCBulletin
The core assumption was that the octopus was primarily intended for use by a buddy as there were a limited number of occasions when such a configuration would be of use to the diver themselves. One of the key recommendations was , as Sophie identifies above, that the octopus should be routed so that it can be presented to an ‘Out of Gas’ buddy in the most comfortable way possible, see diagram below.
Access
Once you have configured your equipment so that it is convenient to use the next, and equally important, consideration is positioning it to ensure that it is accessible for the intended user. For use by the diver themselves this usually means locating the regulator within the ‘triangle of access’, so that it can be seen and accessed by the diver themselves. This can mean having it attached to a necklace or a suitable clip within the triangle.
For use by a buddy there are 2 main interrelated considerations, visibility and identification. In an out of gas situation the buddy should be able to easily see and identify the correct source of breathing gas. For this reason many Octopus regulators are brightly coloured (yellow) and may have corresponding hose colours too. This colouration is pointless however if the octopus is hidden away inside a BC pocket. Locating the Reg within the ‘triangle’ will help keep it visible if an out of gas buddy approaches from the front but consider your normal swimming orientation (horizontal and chest down) and you might find locating an AS in the shoulder area more appropriate.
Think SAFE – Dive SAFE
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