What's the deal with the "Advanced Nitrox" certification?

[Divin'Papaw]

Who did you ask Howard?

As far as accelerated vs optimized decompression, this may help clarify some terms...

DopplerÃÔ Blog

Thanks for the link to your blog Steve. Looking forward to reading your current entries. I've added it to my feed reader as well.

 

[Captain CaveMan]

I just finished up TDI Adv Nitrox/Deco Procedures this past Aug and it only covers one deco gas. They don't currently add a second deco gas until Trimix. Maybe that varies by instructor.

When I took my Adv Nitrox/Deco. I was doing the dive with only one deco gas but carryed 2 bottles. The bottles size was of my choice. I carried a A80 with 50% and a A40 with O2. I used the A80 for most of my dive because of being to L.Wazee you can not get air fills durning the day. So out of 6 dives all were carring the A80 and 2 were with the O2. They were carried on the deep dives for the class.

With TDI manuals they did skip lots of materals, but all the materal missing and with the questions I had Greg/Brett did a great job.
This was the best class I have ever took. Can't wait to spring. Doing Trimix. :mooner:

 

[Divin'Papaw]

When I took my Adv Nitrox/Deco. I was doing the dive with only one deco gas but carryed 2 bottles. The bottles size was of my choice. I carried a A80 with 50% and a A40 with O2. I used the A80 for most of my dive because of being to L.Wazee you can not get air fills durning the day. So out of 6 dives all were carring the A80 and 2 were with the O2. They were carried on the deep dives for the class.

With TDI manuals they did skip lots of materals, but all the materal missing and with the questions I had Greg/Brett did a great job.
This was the best class I have ever took. Can't wait to spring. Doing Trimix. :mooner:

I'm not sure I follow. So you slung two bottles, but only used one of them on any particular dive ... either the 50% or the 100%?

 

[Captain CaveMan]

Yes on 2 of the last dives I slung 2 bottles. a A80 and a A40. I only used the A80 with 50%. I did not use the 100%. they had me carry the extra bottle to get me started for trimix. Since then I did not get to do 2 real switches ( just pratice) but was sudgested to start when I feel ready.
I was had a dive plained this summer to do a 30%mix .60min BT at 120ft. with 50/100%. We got blown out that day.

Bühlmann: Table: ZHL16B Safety: OFF Descent: Immediate GF Lo%: 30 GF Hi%: 85
120Ft
Time 60 30%
70 1(3) 50%
40 3 50%
30 6 50%
20 18 100% 12min on 6 off
Total 29

 

[Blackwood]

Seemed odd to me too. Perhaps he's planning to O2 as a backup for the 50?

Edit: never mind.

 

[battles2a5]

Yes on 2 of the last dives I slung 2 bottles. a A80 and a A40. I only used the A80 with 50%. I did not use the 100%. they had me carry the extra bottle to get me started for trimix. Since then I did not get to do 2 real switches ( just pratice) but was sudgested to start when I feel ready.
I was had a dive plained this summer to do a 30%mix .60min BT at 120ft. with 50/100%. We got blown out that day.

Bühlmann: Table: ZHL16B Safety: OFF Descent: Immediate GF Lo%: 30 GF Hi%: 85
120Ft
Time 60 30%
70 1(3) 50%
40 3 50%
30 6 50%
20 18 100% 12min on 6 off
Total 29

I try not to carry any more equipment that can kill me at depth than I need to. If your instructor just wanted you to carry 2 bottles for the sake of carrying two bottles, why not use a bottom stage, instead? Seems a bit foolhardy for an instructor to suggest multiple gas switches for someone certifed to advanced nitrox/ deco and trained for 1 switch, IMO.

 

[HowardE]

Who did you ask Howard?

As far as accelerated vs optimized decompression, this may help clarify some terms...

DopplerÃÔ Blog

It wasn't you... That should narrow it down

 

[texdiveguy]

Heck, I carry one or multiple bottles on most of my NLD dives, at times I even sling 3-4.....it is for the shear continued practice and skill work. Do I need them on these profiles-NO, do I benefit from the practice of bottle handling-YES.

 

[battles2a5]

I do the same thing on training dives. But doing a skills dive in a quarry and doing a "real" overhead dive using equipment and procedures you aren't trained to use are a little different. I don't know, maybe it's just me.

 

[texdiveguy]

I do the same thing on training dives. But doing a skills dive in a quarry and doing a "real" overhead dive using equipment and procedures you aren't trained to use are a little different. I don't know, maybe it's just me.

I don't recall my TDI Decompression card saying I am limited to the use of only 1 deco gas at that level of training, at the end of my training at that level I was fully able to make 2 deco gas switches.