Low/No Viz bottle management

[ianr33]

Am I allowed to post in this forum?

And that's PLENTY of vis in which to do a gas switch. So what's your point? Have you ever seen ZERO vis mid-water in open water? If so, how did you know your depth?

I've seen ZERO viz in open water.

Zero as in can not read gauges even with said gauge and HID pressed hard on mask.
This was in Lake Travis outside of Austin. Ascending to first deco stops the thermocline was like milk. (All sorts of gunk precipitating out at the interface). We dropped to the bottom and finger walked up the silt a few feet until it cleared.

Where we descended the viz was OK, so the zero viz on ascent was a bit of a shock. If the viz had been that way to the surface we would have been screwed.

 

[Blackwood]

OK ... but how does that address the question posed by the OP ... namely why DIR doesn't do "left-lean, rich-right" positioning.

That wasn't his question.

Q. "So what is the DIR solution to making sure you get the right bottle when the viz is measured in millimeters?"
A. "In open water, it doesn't happen. In a cave, you do this..."

Here's to hoping the squabbling stops.

how do you clearly ID the fact that it's your bottle, and not someone else's?
... Bob (Grateful Diver)

I'm not cave trained, but am interested in the cavers' takes. My off-the-cuff proclivity would be to deco on backgas until the viz clears up enough to verify the bottle contents (and if it's not my bottle, wait around on the surface until the owner exits - likely with mine - and trade).

 

[MXGratefulDiver]

That wasn't his question.

Q. "So what is the DIR solution to making sure you get the right bottle when the viz is measured in millimeters?"
A. "In open water, it doesn't happen. In a cave, you do this..."

Here's to hoping the squabbling stops.

I never attempted to squabble ... but I think I just got reminded why the DIR forum on ScubaBoard is so chronically devoid of anything resembling useful information.

Outta here ...

... Bob (Grateful Diver)

 

[nadwidny]

Where we descended the viz was OK, so the zero viz on ascent was a bit of a shock. If the viz had been that way to the surface we would have been screwed.

But it wasn't like that all the way to the surface and that's the point.

 

[ucfdiver]

but I think I just got reminded why the DIR forum on ScubaBoard is so chronically devoid of anything resembling useful information.

Well, everyone claim's DIR is a system. It's been used on 400ft wreck dives, 7mile cave dives, ice dives in Alaska, and even 20ft reef dives. Most of these entry level topics are fairly well decided by now.

I'm not cave trained, but am interested in the cavers' takes. My off-the-cuff proclivity would be to deco on backgas until the viz clears up enough to verify the bottle contents (and if it's not my bottle, wait around on the surface until the owner exits - likely with mine - and trade).

You have your initials/name on the bottle. I'm not one to believe that true zero viz happens so bad that you can't see your initials. Furthermore, you should have at least some idea of where your bottles were dropped in the cave, because caves that actually silt out THAT bad aren't going to be caves with a lot of traffic. Even at Ginnie/Jackson Blue you rarely see 2 teams bottles within 300-400ft of each other.

 

[ianr33]

And that's PLENTY of vis in which to do a gas switch. So what's your point? Have you ever seen ZERO vis mid-water in open water?

But it wasn't like that all the way to the surface and that's the point.

Question was if zero viz had been seen mid water,not if it had been seen mid water AND went all the way to the surface.

 

[Rainer]

Clearly my implication was that you don't encounter zero vis in open water (while mid-water) such that it precludes an eventual safe and effective bottle switch (i.e. throughout the water column). Your account isn't a counter-example. You obviously did manage to switch. Worst case, stay on backgas awhile longer (and reshape as necessary) as you try to find clearer water.

Question was if zero viz had been seen mid water,not if it had been seen mid water AND went all the way to the surface.

 

[Blackwood]

I'm not one to believe that true zero viz happens so bad that you can't see your initials.

Sure, and if you can read your initials you can also read the MOD marking.

Fair 'nuff.

 

[MXGratefulDiver]

Well, everyone claim's DIR is a system. It's been used on 400ft wreck dives, 7mile cave dives, ice dives in Alaska, and even 20ft reef dives. Most of these entry level topics are fairly well decided by now.

I guarantee you they didn't drop their deco bottles on a 400ft wreck dive.

Yeah, sure ... it's a system. That system involves considering your environment ... not just parroting what the cavers do.

DIR is intended to turn out THINKING divers ... not robots. You're not just supposed to just do it a certain way because "that's the system" ... you're supposed to be able to understand why you're doing it that way.

... Bob (Grateful Diver)

 

[MXGratefulDiver]

Even at Ginnie/Jackson Blue you rarely see 2 teams bottles within 300-400ft of each other.

Yanno ... I ain't even gonna pretend to be a cave diver. So far I've spent a total of six days at Ginnie. And on more than one of those days I saw no fewer than a dozen deco bottles within 50 feet of the sign ...

... Bob (Grateful Diver)