No deco and dive computers

[bbarnett51]

Suunto will indeed clear a deco obligation on ascent.

 

[supergaijin]

lastly, whoever said the suunto will not add ndl as you ascend is wrong.. mine does it all the time. it does it incrementally. if it waited for 1ATM to change, that would be ridiculous... only calculating for every 33 feet.

as i said on both dives last weekend i was on nitrox using an air computer, so i knew i had more ndl time.. I waited until the computer was at 1 min the first dive and started to go up... after 10 ot fifteen feet my ndltime was 5 min..

the second dive i actually went deco on the computer, and as i ascended, i did a stop at 50 feet ( depth was 100) for a few min and looked at the computer and it had cleared the deco and had ndl time listed ...

Computer NDLs are based on specific algorithms. Suunto uses RGBM. I have seen personally Stinger (wife), Gecko (mine) and Zoop (rental) give different NDLs on what is essentially the same dive or series of dives.

NDL and ascents vary according to which theoretical tissue/compartment is controlling the dive. Especially on a second dive where slower tissues are more saturated, an ascent following a dive to the NDL requires going to 2ata or shallower. YMMV according to the profile. From personal experience, when I reach NDLs on typical 60' dives, there is no significant NDL time added until ascending at least 1ata.

For deeper dives where the fast tissues are controlling the dive, a shorter ascent would theoretically give a larger increase in NDL.

 

[lowviz]

There is also the issue of a 'safety stop' becoming mandatory for the same amount of time. This is then reported as a deco obligation.

 

[Griffo]

a few comments to follow up..

first off, the dive shops here all bank 30%, which has a mod equal to the wreck depths here. olympus has 36 for the NOAA guys, but that's it.

remember guys we are at the diving capitol of the east coast... these guys know what they are doing..

they also have the cool carolina rig 15 foot hang line setup... never seen it anywhere else, and I think it is the best way to rig a line..

lastly, whoever said the suunto will not add ndl as you ascend is wrong.. mine does it all the time. it does it incrementally. if it waited for 1ATM to change, that would be ridiculous... only calculating for every 33 feet.

as i said on both dives last weekend i was on nitrox using an air computer, so i knew i had more ndl time.. I waited until the computer was at 1 min the first dive and started to go up... after 10 ot fifteen feet my ndltime was 5 min..

the second dive i actually went deco on the computer, and as i ascended, i did a stop at 50 feet ( depth was 100) for a few min and looked at the computer and it had cleared the deco and had ndl time listed ...

What's so special about the Carolina hang line? I googled it and the images looked just like a granny line. Genuinely curious.

 

[yardpro]

i don't know what a granny line so i cannot compare.

here they run a line down off the bow and stern to 15' deep. the two lines are connected by a horizontal line, making a long line for multiple divers to stop at at the 15 foot depth. there is also a line that runs from where the bow down line and the horizontal safety stop line connect. it goes down to the anchor line at roughly half the maximum depth to give a reference.

i have dove in florida, cozumel, belieze, grand cayman, grand turk, nassau, st thomas, and st martin, and never saw a similar setup... so they are not that common...to me anyhow...

 

[DevonDiver]

Suunto will indeed clear a deco obligation on ascent.

The Suunto will clear deco as you go up. It also adds more NDL.

Incorrect and overly-simplistic.

I've accrued further deco on ascent, using Suunto Vyper and D9 computers. As others have said, it depends entirely on your dive profile, previous dives and ascent speed. The controlling compartment and associated m-value is not a constant that you can assume across each and every dive.

If you were conducting, for instance, repetitive deep dives over a multi-day period, you could have a very nasty shock if assuming 'a little' accrued deco will clear on ascent.

 

[uncfnp]

i don't know what a granny line so i cannot compare.


here they run a line down off the bow and stern to 15' deep. the two lines are connected by a horizontal line, making a long line for multiple divers to stop at at the 15 foot depth. there is also a line that runs from where the bow down line and the horizontal safety stop line connect. it goes down to the anchor line at roughly half the maximum depth to give a reference.


i have dove in florida, cozumel, belieze, grand cayman, grand turk, nassau, st thomas, and st martin, and never saw a similar setup... so they are not that common...to me anyhow...

​From Olympus Dive Center website

To assist divers with their navigation, the Midnight Express and the Olympus utilize an underwater line system. Upon arrival on site, one of the mates enters the water with the anchor and ties it directly into the wreck. He then runs a reel, connected at one end to the anchor line, along the wreck giving divers a large target by which to find the anchor. Directly under the boat at 15 feet are weighted, horizontal hang lines running the length of the vessel on both the port and starboard sides. Towards the bow, the parallel lines form a gradual slope down to the anchor line.
When divers enter the water, off either side of the vessel, they are able to use the line system to make their descent to the wreck. Upon completion of their dive, divers find the anchor, make a gradual ascent again using the line system, and use the hang lines for an easy 15-foot safety stop.

 

[cbm32]

My Suunto Gekko has always accrued addition NDL time and/or cleared deco as I ascend.

 

[DevonDiver]

My Suunto Gekko has always accrued addition NDL time and/or cleared deco as I ascend.

Doesn't surprise me. Does that make it an inviolable rule?... or just that you've not encountered more than a narrow range of parameters?

 

[fbk]

If you were conducting, for instance, repetitive deep dives over a multi-day period, you could have a very nasty shock if assuming 'a little' accrued deco will clear on ascent.

I used to use a Vyper and as a rule never put it into deco intentionally but one of the times I do remember doing it was during a trip doing multiple dives/day... it kept accruing even as I ascended beeping all the way to 6m. It may have behaved differently on other occasions not involving repetitive dives but its been a while since I used one.