DCIEM v Suunto Vyper

[TonyD]

Not sure if this is the right place, but here goes.

Does anybody have any experience of the DCIEM tables, and how much more conservative are they than the Vyper.

Many Thanks.

[benpanter]

I've used them before, and from memory they are incredibly conservative. Fairly sure you can find them online if you look around...

[Bottle Maker]

[quote=TonyD;

Does anybody have any experience of the DCIEM tables, and how much more conservative are they than the Vyper.

Many Thanks.[/quote]

Am asking a question not trolling why would you want tables that are more conservative than Suunto? I thought that the Viper was one of the most conservative computers about in standard form with out using the personal settings.

Graham

[TonyD]

Originally Posted by Bottle Maker

Am asking a question not trolling why would you want tables that are more conservative than Suunto? I thought that the Viper was one of the most conservative computers about in standard form with out using the personal settings.

Graham

SWMBO is now limited to 15m EAD, if she wants to exceed this, use DCIEM air table.

She has a PFO, but has not been told to stop diving, but if she wishes to dive to use the above, this came from Dr P. Wilmshurst.

[Tassie Devil]

Use the SSI Air tables. More conservative again, and easier to use

[manx856]

On a recent 50m air dive i ran DCIEM against the VPM VR3......When i left the water the vr3 still had 42mins of stops left!

Steve

[NotDeadYet]

DCIEM are pretty old tables. The Canadian DND defense archive (it was on the web, not sure if it is still available) has a lot of papers on their development and testing. IIRC they had moved on to a newer model a few years ago.

As the post above shows conservative doesn't necessarily mean longer, how and where the deco is distributed, repetitive diving, allowable ascents, etc., all come into play. DCAP tables have a very good incident rate, something like 1000hrs of trimix diving with no incidences of DCI in one test. Have a search for Tonawanda II or M11F6 models by Hamilton Research, you might have to check some technical journals (IIRC the UHMS journal had some stuff on it) though for any info.

[Gene_Hobbs]

Originally Posted by NotDeadYet

DCIEM are pretty old tables. The Canadian DND defense archive (it was on the web, not sure if it is still available) has a lot of papers on their development and testing. IIRC they had moved on to a newer model a few years ago.

The DRDC archive can be found here. We have permission for their documents but have not added many yet. We are still working with them on getting the papers scanned. Our collection is here.

This table has a ton of bubble data behind it and aims at getting people out of the water with few bubbles. I think this is great when evaluating profiles when a PFO is involved.

Another model that has quite a bit of bubble data behind it is the PADI model. Those papers can be found here.

Originally Posted by NotDeadYet

As the post above shows conservative doesn't necessarily mean longer, how and where the deco is distributed, repetitive diving, allowable ascents, etc., all come into play. DCAP tables have a very good incident rate, something like 1000hrs of trimix diving with no incidences of DCI in one test. Have a search for Tonawanda II or M11F6 models by Hamilton Research, you might have to check some technical journals (IIRC the UHMS journal had some stuff on it) though for any info.

The Tonawanda II model was shown to have some higher grade bubbles on excursions that would be more concerning to me when thinking about a PFO. (Only one paper from CHISAT so far, sorry.)

[TonyD]

Thanks for the info, but SWMBO's only continuing to dive as we had already booked a liveaboard as she/we were convinced that her 2 skin bends were down to poor diving practices on the day.

The probable outcome will be a week of gentle diving ( to restore her confidence) and then stop diving. She gets very wound up over simple things, like dental check ups and the thought of the operation to close the PFO would turn her into a nervous wreck.

Using DCIEM no stop air tables, with nitrox will mean she can gently bimble around, and hopefully enjoy herself.

[Tassie Devil]

I trained and dived on DCIEM tables for 7 years when commercial diving. They are great, however these standard air tables are not designed for decompression diving, they give you conservative bottom times for non-deco dives. The SSI tables are more conservative again and are easier to follow. Plan no-deco dives based around your table and stick to your planned bottom time. Use digital displays to monitor your depth and time accurately and most importanly monitor your ascent rates. The harder the dive, the slower the ascent. Make sure you give yourself a safety stop on every dive as well. I would also be restricting dives to less than 12m if there is an added risk of DCI, maybe not diving at all if the risk is high. As we know, following a table doesn't eliminate the risk of DCI, and some risks are just too great.

MD