"S" Drills

[ae3753]

That added step really doesn't matter at all. There are 2 possibilities: You either have enough or you don't. Period.

Showing the gauge will probably increase your already high stress level as you have now actually SEEN that you have a real, definite limit. By bringing this already implicit thought to an explicit reality, your stress level will actually rise. That's NOT what you need at that moment.

I agree that there are two possibilities - you either have enough or you don't.

However, I disagree that seeing the gauge will increase the stress level. If anything, it should confirm that you ENOUGH gas for exit, and calm everyone down.

Personally, if I was OOG, I wouldn't look at a gauge. However, that's not why I practice unclipping the SPG.

I practice unclipping and showing the SPG for my teammates. In the situation that my OOG buddy wants to see the gas, I want to be able to present it to him efficiently, cleanly, and without issue.

And since this is a drill, the more practice the merrier.

 

[PfcAJ]

You'd be surprised how much seeing that gauge will mess you up.

I was on a dive recently in what became absolutely terrible conditions (nature just didn't want us there) and we had to REALLY tap into that reserve third. I caught a glimpse of my buddy's gauge and seeing that certainly didn't help things. I can't imagine how it would feel if we were sharing gas.

For practice purposes, I suppose its one thing (still not needed), but in real life, you need to be heading for the door in the most expedient manner.

 

[MonkSeal]

SPG should be checked on travel, no need to do it before.

 

[DA Aquamaster]

You'd be surprised how much seeing that gauge will mess you up.

I was on a dive recently in what became absolutely terrible conditions (nature just didn't want us there) and we had to REALLY tap into that reserve third. I caught a glimpse of my buddy's gauge and seeing that certainly didn't help things. I can't imagine how it would feel if we were sharing gas.

For practice purposes, I suppose its one thing (still not needed), but in real life, you need to be heading for the door in the most expedient manner.

Unless the conditions unexpectedly went to hell on the way out in some manner that was totally unpredictable (geologic event, etc), crappy conditions call for turning the dive early to avoid having to tap into the reserve gas. A diver needs to avoid or prevent the problems he can so that the reserve is left intact for the rare problems that can't be avoided or prevented.

Add a catastrophic gas loss to one of the team members in the above scenario and then assess where you'd have been and how many divers would have gotten out alive. You may find you want to re-assess the skills and judgement of the people you were diving with.

 

[PfcAJ]

I'm aware, and the guy I was with was top notch. Geologic events do occur. I'm not going into it, but I can attest to the psychology of that SPG first hand, and thats what I'm trying to get across.

 

[LiteHedded]

Unless the conditions unexpectedly went to hell on the way out in some manner that was totally unpredictable (geologic event, etc)

that's what happened...

I don't need to know what's in your tanks at that point. what does it matter? give me your long hose and head for the door. keep your spg to yourself unless I ask for it.

when the cave tried to swallow aj I know seeing that gauge didn't help matters at all

 

[ivobj]

You'd be surprised how much seeing that gauge will mess you up.

I was on a dive recently in what became absolutely terrible conditions (nature just didn't want us there) and we had to REALLY tap into that reserve third. I caught a glimpse of my buddy's gauge and seeing that certainly didn't help things. I can't imagine how it would feel if we were sharing gas.

For practice purposes, I suppose its one thing (still not needed), but in real life, you need to be heading for the door in the most expedient manner.

Ok, I can partially agree that it can cause some stress to see the gauge, on the other hand the reason of "partially agree" is that, like aa3753 posted, if the gauge shows enough gas, it actually can lower stress levels, but the main reason for using it in the drill, IMHO, is because of the point below:

1 - If you have more than one route choice, for example, you are under deco obligation in open waters and have an OOG situation, after sharing you have have 2 options, if you have plenty of air safety margin you can calmly go back to the ascent cable and start your ascent in a more safe manner, but if your safety margin of gas is short you may choose to deploy SMB and start ascent immediately, although not counting on the safety of an achored ascent cable. To reach that decision you need to consult your SPG and show your buddy so his aware of your choise and the reasonthat motivated it.

2 - If diving in a 3 divers team, common in caves and wreck penetrations, all members of the team, including the one not directly involved in the gas sharing, must be aware of the situation (this includes the gas pressure of the diver donating gas) to monitor and specially for the third diver to be prepared to share his gas as well. As there is one more diver to donate gas, the OOG diver shall not raise the stress level be looking at the SPG.

Of course, during a real situation, I agree that it is up to your judgement not to show the SPG during the share process, but I believe it is usefull to include in the drill to be prepared if you need, specially in the 2 situations described above.

 

[b1gcountry]

After that first dive, we generally do a "modified S-drill" while floating at the surface -- meaning we show each other that our long hose isn't trapped by anything and can be fully deployed, but we don't do the full drill.

What's the point of doing this when the dive's over?

Tom

 

[Rainer]

You are mis-reading. He means they do mod-S at the start of all subsequent dives.

What's the point of doing this when the dive's over?

Tom

 

[DA Aquamaster]

You need to look at the SPG. For example, a three person team goes in and one diver has a catastrophic gas loss. He is now sharing gas with you. If you don't check the SPG initially and periodically the potential exists for you to go OOG as well which would leave all three divers exiting on the third team member's two regs. At best that will slow things down and complicate the exit.

Alternatively if you check and monitor the gas, you'll know that at some point, the OOG diver needs to be handed off to the remaining team member for the remainder of the exit to ensure you retain sufficient gas to exit.