Routing an SPG along the shoulder webbing

[DA Aquamaster]

I don't know about that. I've clipped off tanks and the bolts run down and to the left. The spg would be up and to the right. I also wonder what would be worse, managing the clips on the upper D ring where you can see then or on the hip where you cannot. I'm not even sure the spg needs to be clipped to the chest D ring. I can see it being routed beside the LP hose and secured with zip ties (or cave line if one prefers).

What's simpler. A spg routed beside an already existing hose that can be read without unclipping or adding a 30" hose down the left side of the body that needs to be unclipped in order to be read.

As stated previously, with independent doubles I would route the right SPG along the shoulder strap and it worked well.

In backmount I carry the SPG on the right hip about 85% of the time. The other 15% I tend to carry it clipped to the left chest D-ring - specifically when carrying multiple stage/deco bottles or when carrying a stage at depth or in fairly tight tunnels. While I can fish an SPG out from under a couple stages, or in a tight tunnel, etc, I see no reason to actually do so. It makes sense to keep the SPG on the upper D-ring under some circumstances and having it there also tends to lead to its more frequent use.

Now, the counter argument that you'll get form the DIR crowd is that moving it is not needed and that any suggestion that it is "easier" is just using an equipment solution for a skills deficiency, regardless of whether an actual skills deficiency exists. So in effect, the implication is that you should do the fish it out from under the deco bottle thing because it is harder and consequently doing it will prove you can do it. That is PFS.

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It is true that you should be able to predict what the SPG will read and that is important as any deviation from what is anticipated suggests a problem (leak, roll off, etc, or at least a deviation from the potential plan (slightly higher than expected SAC, etc).

However, too many people take it to the extreme and a subset of those seem to take pride in a doing an absolutely minimal number of SPG checks per dive. I my opinon, that just reduces your SA by eliminating one potential source of information - which is again PFS.

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As for potential confusion between the back gas SPG and the stage SPG(s), they rotate on the end of the hose. If you cannot tell the difference between one near or clipped on the D-ring and one mounted on a stage bottle clipped to the same D-ring, you have serious issues, but even then you can just turn the not in use SPG(s) to face away from you - which will eliminate the confusion - even if you are PFS.

 

[PfcAJ]

In backmount I carry the SPG on the right hip about 85% of the time. The other 15% I tend to carry it clipped to the left chest D-ring - specifically when carrying multiple stage/deco bottles or when carrying a stage at depth or in fairly tight tunnels. While I can fish an SPG out from under a couple stages, or in a tight tunnel, etc, I see no reason to actually do so. It makes sense to keep the SPG on the upper D-ring under some circumstances and having it there also tends to lead to its more frequent use.

Correct me if I read this wrong, but you'd rather have the spg clipped off to your chest in a tight tunnel instead of having it above the lower plane of your body (clipped to the hip), and you'd also rather have the spg clipped off to the chest when you have multiple bottles clipped there too (right next to a fleet of spg's that look just like it), and you mitigate that by just turning it around so you can't see it...

 

[TSandM]

BTW, there is nothing shameful or "newby-ish" about checking your gauge. I was taught to do it every five minutes in my cave class, and to make mental notes of time, depth, prominent cave features and GAS at regular intervals.

I admit that, after some time, you have a good sense of how much gas you use at any given depth, and a good sense of whether you are diving normally or under increased stress. And I'll also admit to having gotten into very sloppy habits as a result of that, combined with the fact that I usually dive with stupid amounts of gas for the dive I'm doing (rarely go below a half tank anywhere). But it is still good practice to check one's gauge regularly.

 

[AndyNZ]

These are incredible answers. We like the spg clipped off where we can't read it without performing supefluos actions. we like it burried behind stage bottles, we like it here becuase if you dive completely different from the way you dive now, it will not work.

Not quite sure where you get the last part from - if you'd bothered to read my earlier posts, you'd see that I'd comments that a variety of rebreathers route SPGs in a similar manner to the way Dale is suggesting, and acknowledging that it makes it easy to look at. If that is the only goal, then great.

You'll also find that I used to do something similar but have chosen not to do that any more, never have I said that it won't work.... just that it doesn't work for me.

In terms of the SPG being buried behind stage bottles, it's not - the clip is always on top of the other clips, all you need to do is reach around exactly the same as if the stages weren't there and that's where the SPG is - I don't have to rummage around. Sure, it takes some degree of procedural thinking when you clip stuff on and off, but that's the same as what I've got going on elsewhere. Clips on my right shoulder d-ring are always in the same order, from inside to out - spare double ender, backup light, primary light then primary reg. With a little bit of practice, you don't need to think where anything is, and it just comes easily.

The problem is, that different people are working from different assumptions - not meaning to put words into Dale's mouth, but he is very much self-focused (as a solo diver) and as such is thinking of what he is doing now for him. I am not in that space, instead, I am looking to maintain consistency in how I dive.

For example, my question about Dale diving independents - he replied:

For ID's I would just route one down each shoulder. That is what actually got me to thinking more about it as one thing I don't like presently is the loops my SPG's make when clipped off to my chest D rings. Nor how they sit out a bit in front. The miflex idea is a good one - hadn't thought of that actually.

My take is that for a single tank, he would route the SPG down the LPI hose. For independents, the right SPG would somehow come over the right shoulder and presumably be clipped off on the right should d-ring. Well, why not do the same on the left and not route it down independently from the LPI - you then have symmetry, plus consistency between single and double rigs.

I won't do that - I already have four clips on my right shoulder d-ring, a fifth takes it over the line into being too congested. But if it works for Dale, then he can go for it.

Anyway, back to the SPG - my question regarding the assumption that you need to read it. If Dale is diving independents, he *has* to check his SPGs.... there is no other option if he wants to maintain a gas reserve (correct me if I am wrong, Dale). I was pointing out that the mindset of having to check gives rise to an assumption. I don't have to check, on a routine dive that's planned, being self-aware enough to know that it's all going tickety-boo.... I can choose to check, but I don't need to check.

So I think you need to lighten up - to my mind, challenging assumptions is perfectly acceptable behaviour. If someone wants to ignore my posts, they can. If it stimulates a thought in someone, then great.

 

[djcheburashka]

These are incredible answers. We like the spg clipped off where we can't read it without performing supefluos actions. we like it burried behind stage bottles, we like it here becuase if you dive completely different from the way you dive now, it will not work. And hell you don't have to use the thing very much anyway, when everyone knows that running out of gas is a very serious and common problem for many diving accidents.

Not one decent answer why not to do it clipped to the inflator hose, in my opinion.

I will try to give some decent answers:

1. The OP's theory was that he could use a shorter HP hose and route it alongside the inflator. One problem with this is, the way you show your buddies how much gas you have in an OOA rescue situation is by showing them your SPG, which has to be long enough for you to do that. 30" (or 24" for some people) on a hip mount is just long enough. So either the OP's plan leaves a lot of HP hose sticking out somewhere or you can't show the gauge to your buddy.

2. A second reason is, if the inflator hose is the right length then attaching the SPG to it doesn't actually make it much easier to see or use. The inflator is supposed to be quite short, and I at least have to turn my head and look to see mine. Add to that that the SPG twists on its hose, and you're going to have to put a hand up there to look at it anyway. So you're not really gaining much in ease or speed of use, at least unless the issue you're trying to solve is getting the SPG out when you're wearing stage bottles.

3. Routing the HP hose down and under the shoulder to the hip (likely behind stages), instead of over the shoulder along the corrugated hose, gives the HP hose additional protection from abrasion and sharps and so forth.

4. There are a variety of failure modes in which the SPG could get in the way, or at least add to task loading. Freeflow of the low pressure inflator hose, for example. Or LP inflator hose failure requiring oral inflation of the BC. You wouldn't want the SPG banging around during that.

 

[dumpsterDiver]

I will try to give some decent answers:

1. The OP's theory was that he could use a shorter HP hose and route it alongside the inflator. One problem with this is, the way you show your buddies how much gas you have in an OOA rescue situation is by showing them your SPG, which has to be long enough for you to do that. 30" (or 24" for some people) on a hip mount is just long enough. So either the OP's plan leaves a lot of HP hose sticking out somewhere or you can't show the gauge to your buddy.

2. A second reason is, if the inflator hose is the right length then attaching the SPG to it doesn't actually make it much easier to see or use. The inflator is supposed to be quite short, and I at least have to turn my head and look to see mine. Add to that that the SPG twists on its hose, and you're going to have to put a hand up there to look at it anyway. So you're not really gaining much in ease or speed of use, at least unless the issue you're trying to solve is getting the SPG out when you're wearing stage bottles.

3. Routing the HP hose down and under the shoulder to the hip (likely behind stages), instead of over the shoulder along the corrugated hose, gives the HP hose additional protection from abrasion and sharps and so forth.

4. There are a variety of failure modes in which the SPG could get in the way, or at least add to task loading. Freeflow of the low pressure inflator hose, for example. Or LP inflator hose failure requiring oral inflation of the BC. You wouldn't want the SPG banging around during that.

1, Maybe it would be harder for your buddy to see it, I'm not sure.

2. Either he can read the guage or not while on the inflator hose. I'm pretty sure my eyes are so bad that I couldn't read the gage that close to my face. Also, I try to NOT twist pressurized pressure guages, oce they are turned in the right direction, they tend to stay in that position, at least my crusty ones don't spin like a pinwheel when pressurized.

3. Additional protection seems inconsequential. We all know that a damaged HP hose is relatively trivial while a torn lp hose is not. So if the two hoses (lp and HP) are being routed in the exact same manner, i don't see a danger. In other words, if over the shoulder routing is recommended for the vunerable LP hose, how is it wrong for the HP hose?

4. Failure of the LP inflator occurs much less frequently than checking of the SPG. I honestly don't see an obvious problem with oral inflation if the SPG is attached.


Someone else brought up the issue of if the LP inflator stuck on, and the diver desired to fold the hose rather than dsconnect the hose, then the two hoses routed together might complicate that maneuver. THAT seems to me to be a potentially viable concern, but on the other hand you, hp hose is usually a lot stiffer than the lp hose and I imagine they difference will be discrenable.
4.

 

[Blackwood]

In terms of the SPG being buried behind stage bottles, it's not - the clip is always on top of the other clips

I keep mine underneath the other clips, not on top of them.

Bottles float up, my SPG does not.

 

[DaleC]

At least it beats the old "splits vs paddles debate".

I don't think you are puting words in my mouth Andy. I've said before that I dive with a variety of divers and rigs and that the development/experimentation/research part of diving really appeals to me. Looking at something in a different way does not stress me out. Half the time I'm either crazy or reinventing the wheel but that's also half the fun. I'm enjoying my hobby and I hope everybody else is too!

I can also understand that for some the emphasis is on preserving standardization against encroachment by those who think they know a little better but that's not my game here. I know the basic HOG rig works well and I'm not challenging the efficacy of already defined SOP's. I have no problem reading my spg the way it is.

Sometimes though, I just can't help but try to rearrange the furniture.

 

[AndyNZ]

I keep mine underneath the other clips, not on top of them.

So you just reach over the bottles and underneath? My arms are pretty short, I'd probably struggle to get around two AL80s in that way.

I'm mostly diving with deco tanks rather than stages, so by the time a tank gets floaty I'm not really worrying about the backgas SPG. I can see the advantage with stages - but then I tend to get mine out of the way once used.

Nice idea, though, will have to give it a go and see how it works - thanks.

 

[JeffG]

So you just reach over the bottles and underneath? My arms are pretty short, I'd probably struggle to get around two AL80s in that way.

I'm mostly diving with deco tanks rather than stages, so by the time a tank gets floaty I'm not really worrying about the backgas SPG. I can see the advantage with stages - but then I tend to get mine out of the way once used.

Nice idea, though, will have to give it a go and see how it works - thanks.

I do it like you. I find it easier to put my arm between my body and the deco bottles to find the spg (and its clip)