A need to rehash our discussion on primary donate

[Diver0001]

As most of you know, and likely agree, I am a firm proponent for primary donate.

Ok.... so what is "Bogaerthian". We're not starting on revisionist histories, now, are we?

As for the primary vs. secondary discussion:

1) I have no real opinion about sidemount other than that it comes across to me as a more complicated solution to the problem that backmount solves perfectly except in very specific circumstances.

A la.... if you need to share air from a sidemount configuration then donating the primary seems like the way to go. At least you know that you can breathe whatever the other diver has in his/her mouth.

2) As for rebreathers. I have several buddies who have them and none of them dive without some kind of a bail-out, which is also YOUR bail out if push comes to shove. So there too I don't see the need for complicated discussions.

Maybe I'm missing something but if I am it is probably highly context dependent and therefore something that needs discussing before the dive.

R..

 

[tbone1004]

@Diver0001 Bogaerthian is what the razor guys call their hose routing, but it's basically short hose left, long hose right.

Point of starting the discussion was to see if it is worth looking at sidemount hose routing again to allow for primary donate, or if it was even a critical discussion for these types of gear configurations, especially with CCR coming out of the closet and being pushed lately.
I think primary donate is the obvious winner in backmount-single hose diving, but it is something that we have to contend with in sidemount and CCR. Sidemount has a couple ways to solve it, but CCR doesn't.

 

[Diver0001]

@Diver0001 Bogaerthian is what the razor guys call their hose routing, but it's basically short hose left, long hose right.

Razor guys? I'm out of my depth here. Is that some kind of side-mount configuration?

R..

 

[tbone1004]

Razor guys? I'm out of my depth here. Is that some kind of side-mount configuration?

R..

yes. the original commercially available mexico-style rig IIRC. Largely displaced with the xDeep, but most of those guys still use the hose routing that Steve came up with however many years ago. Edd uses a similar configuration, but SPG's are up instead of down, and the inflators are not on the end of the turrets

 

[Diver0001]

Well.... as I said, I'm out of my depth when it comes to discussions of side mount. I don't dive in caves (the only place it really seems to me to make any kind of sense) and all of the ocean divers I've seen using it to date look a little ... well ... like they've found an "engineering" solution to a problem that needed a bigger dose of common sense.

... and I do admit here that I don't know what I don't know about this config because I don't dive in a context that would make it make any sense....

The elephant in the room, of course, is to wonder why the left and the right sides would be configured differently. You have *one* regulator in your mouth and if you're in a cave you may need to donate that to a diver that can't come along side..... so to me it seems more logical to have a long-hose on both sides because of that and to find some way to route it so it doesn't become a jumble of chaos, which from my limited experience, is what sidemount looks like to a layman.

R..

 

[AJ]

You have *one* regulator in your mouth and if you're in a cave you may need to donate that to a diver that can't come along side..... so to me it seems more logical to have a long-hose on both sides because of that and to find some way to route it so it doesn't become a jumble of chaos, which from my limited experience, is what sidemount looks like to a layman.

The only situation a sidemount diver would have to share in a hurry (oog) is when diving with (single tank) backmount divers. Sidemount divers do carry their own bailout (totally independant doubles). Losing all of the gas in both cylinders in one instance is almost impossible. Well, maybe when struck by a boat but one will have other worries than gas in that situation. Finding their body parts for instance.

Handing of the cylinder to the diver out of gas is an option in sidemount (aka stage cilinder). Therefore two long hoses are not really needed. Even one long hose is questionable in sidemount. Bailout in sidemount is meant for their single tank diving buddy, not for the sidemount divers themselves imo at least.

 

[tbone1004]

@Diver0001 the argument for maintaining primary donate has been kept by the two agencies that still teach DIR. UTD came up with the z-manifold to maintain what is essentially a normal doubles configuration, and ISE uses what is essentially stage bottles.
The biggest issue with sidemounting double long hoses is that you can't put the regulator hoses behind your neck. If you have Poseidons that are non-directional it helps a little bit, or even Apeks/Dive Rite's that are switched, but the hoses have to come straight up to your mouth. In a true sidemount restriction that increases the change of the hose being pulled out of your mouth if it catches on something, and on a scooter it can cause jaw fatigue issues.

Part of this comes down to a situation about diving with mixed teams that @PfcAJ weighed in on a bit earlier. If the whole team is in sidemount, you shouldn't have to ever share gas. If the whole team is in backmount, you have a long hose. If the whole team is on a CCR, you should never have to share gas. In a cave, unless you're doing expedition type diving, there is a risk of coming across a diver that is not part of your team and needs gas. In that case, IMO diving without a long hose is irresponsible. That applies to both sidemount and CCR diving. In a cave, we have the advantage of lights which usually give us enough warning that you are unlikely to get mugged.
In OW, I don't think sidemount is ideal, so I dive doubles and don't have to worry about it. When I dive a double hose however, I have just had to come to terms with not being able to donate the primary.

 

[rjack321]

To me if I am carrying 2x 85s or more of BO gas in a cave it seems rather silly to not be able to share some of that with anyone who needs it. By a buddy on a "project" who in theory has all their own gas but maybe its taking longer or siltier than we ever imagined to exit. Or a mugger. Hence one long hose just like in typical OC sidemount configuration.

 

[JohnnyC]

With a double hose reg, I do a 40” hose with the reg stowed in an octo retainer. It’s fine.

That was actually the original plan, but I didn't have an octo holder handy and had some bungee and I just left it.

I should revisit it, but it's packed away until I'm back from Japan anyway so meh.

 

[tbone1004]

That was actually the original plan, but I didn't have an octo holder handy and had some bungee and I just left it.

I should revisit it, but it's packed away until I'm back from Japan anyway so meh.

I've been using these
Store | Vintage Double Hose

I put them on all 3 of my backplates as well as my sidemount rigs. Convenient on the left side in backmount to keep the inflator sorted out, but since I use Jetstreams for all of my OC stuff, They hold onto the showerheads really well. Never tried with a "normal" regulator, but may be worth trying