Going into deco

[redacted]

What a waste. just pull out the battery.

Surprise. I was trying to help some divers with their Sunnto (I believe) and intended to pull the batteries as a last resort. But the manual indicated that gas loading data was retained even with battery removal.

 

[miketsp]

I think one of the head-shaking things about this particular set of dives is that we had five divers in the water, doing similar or identical profiles, using several different computers or other methods of dive planning/monitoring, and four of us came out quite happy about the decompression aspects of the dive. One did not. And not only was that computer unhappy, it was TWENTY TWO MINUTES unhappy.

Now, I know decompression is not a science, and I've read extensively enough to understand that various algorithms will generate significantly different answers about no-decompression time, or required deco. But this seems to me to be an egregious example of the possible variation.

I really like the way I have learned -- I do deco on EVERY dive, and plan for it. It becomes habit, and I'm sure it increases my safety.

Don't forget that the Suunto penalises you heavily for any sudden depth changes and these will not necessarily show up on the post-dive log due to the normal sampling interval of 20 seconds for logging.
Since my wife & I started diving with the same model of computer (Vyper) these effects became more obvious. If I dive with both computers on the same arm they read identically throughout the dive otherwise....

Also the red triangle at the start of dive 2 indicates that a little more SIT would have reduced the deco obligation significantly.

 

[Blackwood]

But the manual indicated that gas loading data was retained even with battery removal.

Not if it's still wet while you remove it

 

[lamont]

What a waste. just pull out the battery.

just bend it.

it'll beep for awhile and then eventually shut up and be perfectly useful in gauge mode.

 

[Hemlon]

Here's a question:

If someone on SB posted that they had not only went into deco numerous times, but also plan to do it in the future, could DAN refuse to pay claims?

For example, if a person used their own name as their SB username and reported a DCS incident, could a DAN representative read the post (and several of their old posts) and refuse to pay their claim?

I know that several equipment manufacturers frequent this board...do DAN reps frequent it also?

 

[Cheekymonkey]

Funny, when I tried to reset my oceanic the manual says the samet hing about the hot swap time limit. Which was in the seconds range, I kept mine out for 10 minutes, and when I put it in it was still bent, don't ask... I have no idea

 

[Blackwood]

Here's a question:

If someone on SB posted that they had not only went into deco numerous times, but also plan to do it in the future, could DAN refuse to pay claims?

For example, if a person used their own name as their SB username and reported a DCS incident, could a DAN representative read the post (and several of their old posts) and refuse to pay their claim?

I know that several equipment manufacturers frequent this board...do DAN reps frequent it also?

I haven't read my DAN literature in quite a while. Does it say somewhere that one can not plan past-NDL dives? Further, does it define NDLs that can't be exceeded?

 

[lamont]

One thing to keep in mind here is that this dive wasn't a 20 minute dive to 160 fsw using 21/35 and staged decompression with EAN50 for 20 minutes. Generally when people talk about "dont do decompression dives without training" they're referring to trying that without the proper training and equipment.

And even that deco profile is still not "a lot" of decompression. If you can avoid a rapid ascent on that 160 fsw dive and do something resembling a decompression curve you should get out of the water okay. This kind of 'decompression lite' of going into a couple minutes of deco on a computer on a recreational dive to normal recreational limits is a very mild decompression risk.

Still, most recreational divers shouldn't be doing this. Most of them can't do a midwater OOA even within +/- 10 fsw or shoot a bag midwater to those tolerances or anything. They have bad gas management skills and buoyancy control. They should be steering clear of the NDLs. They also will follow their computer blindly and not shape the curve at all and will wind up bent.

Considering that you've both been cavern diving, though, these profiles are not very concerning. With a little bit of deco on an otherwise recreational profile you are still only a breath away from the surface, even though you may have a 5-10 minute soft overhead. And even if you blow off the last couple minutes of deco if you can spend 3-6 minutes on a slow ascent it'll let your faster tissues offgas so that if you do get hurt you won't get hurt bad. A cavern is a bit worse. There you're a couple minutes away from the exit and its more than a breath away (at least it was in the cavern zone in Taj). So if diving in a cavern was okay, so was this dive...

 

[lamont]

I haven't read my DAN literature in quite a while. Does it say somewhere that one can not plan past-NDL dives? Further, does it define NDLs that can't be exceeded?

preferred and master plans have no limits:

http://www.diversalertnetwork.org/insurance/compare.asp

the standard plan limits depths to 130 fsw / 40 msw.

(doesn't say anything about if a 70 minute bottom time at 100 fsw would be covered or not... i would assume not unless i had a lawyer look over the fine print...)

i signed up for the preferred plan back before i ever thought about technical diving just because it seemed like for an extra $45/yr i could avoid expensive $10,000+ questions after an accident...

 

[Hemlon]

I haven't read my DAN literature in quite a while. Does it say somewhere that one can not plan past-NDL dives? Further, does it define NDLs that can't be exceeded?

I don't know if it does either. But my guess is that it requires you to dive within your training/certification level. So if one is INTENTIONALLY going into deco w/o being tech trained, I would guess it could impact your coverage.