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Why the long hose?

There are many differences in the way a recreational and technical diver configure their equipment. One of the most distinctive aspects of a technical diving setup is the use of a long hose on the primary regulator. A typical recreational diver will have their main regulator and then an ‘octopus’ regulator which can be donated to their buddy in case of emergency. This octopus reg is often, but not always, on a slightly longer hose than the main regulator. Technical divers tend to use a much longer hose, from 1.5m to 2m in length. There are a number of reasons for this. When diving in an overhead environment such as a cave or inside a wreck then if one diver were to go out of air (OOA), it may be difficult to swim out whilst in the side by side position that a normal length octopus would require. With a long hose, the divers can be one in front of the other and so can easily swim through restrictions.

Of course, most recreational divers will never go anywhere near a cave or carry out any level of wreck penetration but a long hose is still useful, even in an open water environment. In an OOA situation you will need to be very close to your buddy if they have a traditional octopus. Most OOA drills are carried out in calm conditions with both divers kneeling on the bottom of a pool or on a convenient bit of sea bed that the instructor knows is ideal for this drill. Once the OOA diver has taken a few breaths the instructor signals that the drill is over and the dive continues. Unfortunately this isn’t very realistic. In a real OOA situation you may need to remain neutrally buoyant as there may not be a convenient patch of sand immediately beneath you. If one of you is OOA then you will need to ascend to the surface. If you try to ascend while breathing off your buddy’s short hose, you will need to be very close together. Sending up a delayed SMB, controlling the ascent and holding a safety stop are much more difficult when you are very close together and ‘in each others faces’. Combined with the stress of the initial OOA this can be enough to turn a difficult situation into a full blown incident.

On a no-stop dive this may cause problems and will be inconvenient. Controlling the ascent rate and holding a three minute safety stop will not be easy. It is for these reasons that OOA situations are often associated with rapid or uncontrolled ascents. An uncontrolled ascent is bad enough on a no-stop dive. However, if you are doing a decompression dive and have mandatory decompression then it is simply not an option.

The use of a long hose enables you to be slightly further away from your buddy. This gives you the space to perform all of these tasks with enough room to remain comfortable and composed. Once you have passed over your regulator and deployed your long hose you can maintain your normal in-water position and the ascent is then no more difficult than if your buddy was breathing their own regulator.

The use of a long hose is closely associated with technical diving and is often seen in conjunction with a twinset. However a long hose is not restricted to a twinset and it is possible to use this configuration even on a recreational single cylinder set up.

The long hose could go on the octopus but most technical divers put the long hose on their primary regulator. This is because in the case of an OOA they would plan to donate the reg in their mouth. This is not what the majority of divers were taught on their entry level course so why should this method be adopted? The first reason for donating the regulator in your mouth is that you know this regulator is working. The OOA diver will be under stress and putting a working regulator in their mouth is the quickest way to calm them down. Another reason is that many people believe that an OOA diver is more likely to take the regulator from your mouth rather than hunting around for an octopus.

The last reason is that technical divers frequently carry multiple cylinders. These cylinders carry gasses which are only breathable at certain points of the dive. If you breathe the gas at the wrong depth then Oxygen toxicity could be a very real risk. We know that the reg in our mouth always contains breathable gas and so by donating this reg we are ensuring that the OOA diver is getting a safe source of gas.

Of course if we donate our reg then that leaves us with no reg. This is not a situation that we want to be in for very long. If we now need to start hunting around for our backup, ensuring that we don’t take a deco gas reg by mistake, then we are just moving the problem along from the OOA diver to ourselves. For this reason the technical diver does not store his backup in his pocket, dangling by his hip or clipped somewhere on his chest but instead he stores it on a bungee around his neck. This means that once they have donated their primary it is just a question of ducking the head and putting the bungied backup into their mouth.

Using a long hose is sometimes criticised for being non-standard or even confusing, especially when training new divers. I have always found that a good buddy check, where you explain your kit configuration, is very effective at removing any queries. This is especially true for new divers. After all, as all of the kit is new to them they don’t know whether your kit is standard or not. In many cases new divers are the most open to the long hose configuration as they are not preconditioned to think of the standard configuration as the only option.
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Mark Powell
Dive-Tech: Technical Diver Training
http://www.dive-tech.co.uk