The Basics
Webbing a Harness
Stages & Deco
Gas Choice
Single Cylinders
Scooter Prop

Hose routing

The idea is to have no adapters on the first stages, but to run the hoses straight from the first stage ports, straight down, and then off to their routing. In general we do use strain relief's as this prevents the hoses "whistling" around in any flow (like hanging on a shot line during deco).

The Fundamentals
The hoses are routed and used as follows : The diver breathes off the long hose (see here for a debate why) which comes off of the first stage on the right hand shoulder post (as worn). The long hose is ran down the between wing and right hand cylinder in a straight line, under the light canister (see lights), upwards in a diagonal direction across the chest, behind your head and in your mouth from the right - when diving the hose will float and stay tight in against the chest. This hose must be the last thing put on so as to not to be fouled by anything else, thus preventing a clean deployment in an out of air situation . One thing about that hose - it floats; so you really don't need to do anything special with it when you are not wearing a light.   In this case it can go under the knife, which is on the belt , or just have a little of the hose tucked into the belt, if it is bothering you when you are upright in the water.

One key point is that the long hose is not bungee'd anywhere - no matter where / how bungee is used it slows down a deployment - try getting a bungeed hose out to donate to an OOA diver in under 2 seconds - that's all this system takes - duck head and give main regulator - diver now has gas - flip remaining two feet of hose clear from weight belt or from light with thumb - diver now has 7 feet of hose for exit through cave (or wreck). Stuffed hoses have a habit of getting caught on things and either trap you the diver or pull free and then float about.  When this happens there is no convenient way to restow the hose and it generally takes two divers to to restuff it.

The left hand shoulder post has a first stage which carries the backup regulator, it's hose goes behind the neck(where you can hear if it is leaking) and the contents gauge - the contents gauge clips off with a piston bolt to the D ring on your left hand waist strap. The backup regulator hangs under your chin on a length of surgical tube, so if your buddy runs out of gas and you donate the long hose regulator, you know exactly where your regulator is.  This tube is attached to the regulator mouth piece using the same zip tie/cable tie as the mouth piece. It's good practice to check this regulator regularly during the dive, just pop the regulator on the long hose out of your mouth and take a few breaths off your backup regulator - this is protecting your own life as this is the regulator you will be breathing off if your buddy runs out of gas.

Hoses should be exact lengths, like 26" for the high pressure hose so it will be possible to run without bowing, from the left first stage (as worn) to the left hand waist D ring.  In general any shorter and you can't read the gauge, any longer and it is not streamlined. The backup regulator hose must come from the left post and feed around to the mouth from the right hand side. There can be an elbow there to make it lay evenly, but no swivel.

Almost any regulator can be made to run the hoses properly. You need not pay any attention to the "R" ports - see the page on regulators. Any post on a good regulator will deliver more than you need, unless you are running power tools with it, or a paint sprayer, or a haskel pump

The "Original" way

The maximum number of hoses possible cross behind the neck, this is so that you can hear a leak - your head transmits the sound perfectly, and the flow in the hose from even a pinhole leak will be heard as regulator action and air moving. This is not needed with the hp hose (to the contents gauge), as those leaks are so loud.
The diagram show how hoses can be brought off the Scubapro MK20 first stages which have a regulator port in the end of the first stage - as can be seen this makes for neat hose routing. The first stage on the RHS of the diagram (ie the LH valves as wearing the set) has the backup regulator coming out of the end port, the HP hose is the one heading straight down to the right of the diagram.  The diagram does not show a dry suit inflate (as I was set up for argon when I took these pictures), however if using back gas for suit inflation, the dry suit inflate would come off the same valve, coming out of one of the bottom facing turret ports and following a similar line to the HP hose. The RH (as wearing it) first stage (on the LHS of the diag) has the long hose and the wing inflate, which comes out of the bottom port.  The reason to route the hoses this way is that when gas sharing the long hose can swivel around and point straight up (ie towards the OOA diver who is leading), this would allow two divers exiting a wreck or cave to have the maximum long hose lenght available in this stressfull scenario.  This first stage does not need a HP hose as we only use one contents gauge.
As can be seen the wing corrugated hose is replaced with a shorter hose (about eight inches long) so that the
inflate sits right on the top of the shoulder and is held in place just above the D ring with a piece of bungee, The halcyon wing comes with the correct lenght hose. With the inflate up here the hose/inflate assembly does not need to be moved to inflate/deflate thus putting less stress on the wing/hose assembly and on the hose/first stage.  The advantage of rigging this way is that whilst we are succesfully breathing off the long hose we know we have bouyancy.  The wing inflate is also on the valve which cannot be rolled off if we bang into the roof


Dsc00007.jpg (51155 bytes)

An Alternative Method

A second way of rigging the hoses has been proposed by other groups diving in cold water, The aim in this routing is to separate the wing and the long hose from the same first stage.  The concern is that when descending and inflating the wing, the LH first stage could freeze.  However I have never suffered from any problems myself (rigged "the original way " and diving in UK winter waters). This method of hose config is shown for interest only, the wing inflate is ran from the left hand post on a very short hose , as seen in the photograph to the left. Again the wing corrugated hose is replaced with a shorter hose. This requires that the hose from the first stage is also very short (again six to eight inches long) - no excess hose is then needed to be tied down / routed. The photo to the right shows the HP hose, with the contents gauge clipped onto the waist D ring


The LH picture shows the backup regulator and how its hose would sit when the regulator hangs under the chin. The dry suit inflate hose (if not using Argon) then comes off the right-hand side The RH picture shows the systems with the long hose attached as well. Notice how the APEX first stages have been laid on their sides so as to help the hose routing by driving the hoses straight down and not out over the shoulders.


Why Breath the long Hose - Adopted from an article by Steve Irving
In the DIR system it is believed that the only reasonable conclusion after weighing all the evidence, is that a divers primary regulator should be the one attached to the long hose. First, we all agree that the reason for the long hose is to facilitate the safe exit from a cave/wreck/dive in an emergency situation. The extra length being to allow for restrictions and limited viz. etc as well as increased comfort on a decompression stop. We purchase the long hose in hopes we never put it to use in an emergency, but it is there when needed. We all agree that gear intended for emergency use, must be working, and immediately accessible. We must assume the out of gas diver became aware of his/her present condition, after exhaling and then trying to pull a vacuum on their cylinders. Panic, even for the trained diver is only seconds away. They need gas, and they need it now. They need pure gas, no water. They need a regulator that's! They don't have time to remove a small twig, or piece of debris from the exhaust diaphragm.We agree that the regulator that you are breathing, is working right now. If it's not, you called the dive, or fixed it. We also agree that there is no way of knowing if the regulator you are not breathing is working right now.You checked it at the beginning of the dive, and you checked it a few minutes ago - didn't you, but right now we really don't know. If that regulator is fouled and needs clearing, who's in better shape to deal with it? The out of gas diver is probably not right next to you, he/she has signalled you, got your attention, and has indicated that they are out of gas. You both beginning swimming towards each other. Now is the time to go to the back up. You have time, they don't. What if they are right next to you. They don't signal, they just grab, and you don't have time to give. You are still in better shape. You have gas. And which regulator do you think they will reach for? Unfortunately not all divers keep their alternative second stage in the same place. We can agree however, that all divers do keep their mouths in the same place. Which regulator do you think they will grab? Some argue that by passing off the regulator you are currently breathing from, causes two divers to be temporarily out of gas, and this is a problem. If you can not remove a second stage from your mouth, and replace it with another, should you be diving? Think about it - this is basic stuff.

Many will also contend that the long hose increases breathing resistance and thus choose to breath from the short hose. A quality regulator that is properly adjusted will deliver more than adequate gas supply, even through along hose. If it doesn't, then how is your buddy going to react when he tries to take a few hits from it in a stressed state? What it comes down to is this; are you willing to save your buddy by passing the best breathing, and guaranteed working regulator when he/she needs it? It's just not a good idea to plan a dive, that when someone runs out of gas,you pass them a regulator that worked....last time you checked

Other Hose considerations
We have yet to source custom length HP hoses in the UK - if you know of a source please email me.

All Low pressure hoses are also the exact length - Low pressure hoses can be custom ordered in any length from Runnymede Dive,

Copyright © 2001 [Gas - Diving]. All rights reserved.
Revised:2 July, 2001