Which mixes for trimix are better for 330 feet (100 meters)?

[Tomeck]

Why don't you post your dive plan for this dive?

Sorry, it is not in English, but I think you can understand. I use V-Planner. This is not my plan for this dive, but only a question.

Intervalle de surface = 1 jours 0 hr 0 min.
Altitude = 429m (c)
Conservatisme = + 3

Desc à 100m (10) Trimix 14/50 10m/min Descente.
Niveau 100m 5:00 (15) Trimix 14/50 1.52 ppO2, 40m ead, 45m end
Rem. à 66m (18) Trimix 14/50 -10m/min Remontée.
Palier à 66m 0:36 (19) Trimix 14/50 1.05 ppO2, 24m ead, 28m end
Palier à 63m 1:00 (20) Trimix 14/50 1.01 ppO2, 23m ead, 26m end
Palier à 60m 1:00 (21) Trimix 14/50 0.97 ppO2, 22m ead, 25m end
Palier à 57m 1:00 (22) Trimix 14/50 0.92 ppO2, 20m ead, 23m end
Palier à 54m 1:00 (23) Trimix 14/50 0.88 ppO2, 19m ead, 22m end
Palier à 51m 1:00 (24) Trimix 14/50 0.84 ppO2, 18m ead, 20m end
Palier à 48m 1:00 (25) Trimix 14/50 0.80 ppO2, 16m ead, 19m end
Palier à 45m 1:00 (26) Trimix 14/50 0.76 ppO2, 15m ead, 17m end
Palier à 42m 2:00 (28) Triox 30/30 1.54 ppO2, 16m ead, 26m end
Palier à 39m 1:00 (29) Triox 30/30 1.45 ppO2, 15m ead, 24m end
Palier à 36m 1:00 (30) Triox 30/30 1.36 ppO2, 13m ead, 22m end
Palier à 33m 1:00 (31) Triox 30/30 1.27 ppO2, 11m ead, 20m end
Palier à 30m 2:00 (33) Triox 30/30 1.18 ppO2, 10m ead, 18m end
Palier à 27m 2:00 (35) Triox 30/30 1.09 ppO2, 8m ead, 16m end
Palier à 24m 2:00 (37) Triox 30/30 1.00 ppO2, 7m ead, 13m end
Palier à 21m 3:00 (40) Nitrox 50 1.52 ppO2, 9m ead
Palier à 18m 2:00 (42) Nitrox 50 1.37 ppO2, 7m ead
Palier à 15m 4:00 (46) Nitrox 50 1.22 ppO2, 5m ead
Palier à 12m 5:00 (51) Nitrox 50 1.07 ppO2, 4m ead
Palier à 9m 8:00 (59) Nitrox 50 0.92 ppO2, 2m ead
Palier à 6m 11:00 (70) Nitrox 50 0.77 ppO2, 0m ead
Palier à 3m 21:00 (91) Nitrox 50 0.62 ppO2, 0m ead
Surface (91) Nitrox 50 -10m/min Remontée.

 

[Tomeck]

If you have a choice between 50 and 100, can you not bring both?

It is a good idea to have 50 and 100, but if I have only three mixes?

 

[Blackwood]

I don't have any experience at that depth, but what I was asking is: why are you limiting yourself to two deco gases?

You have a LONG way to go from the bottom to your first bottle if it's 30/30.

 

[jtivat]

Which mixes for trimix are better for 330 feet (100 meters)?

I think three mixes 14/50, 30/30 and 50, is it a good idea, if the limit of ppO2 is 1.6 for the MOD?

I would not do this dive.

Your bottom gas is wrong I would use 12/60 14 is way too high for 330'.


For sub 250' dives depending on the BT you should be thinking of three deco gases. For sub 300' in my book three gases are mandatory.


Your first stop is going to be at 250' ish do you really want to use 12% or even 14% from 250' to 130'??

Then you are missing 100% I do a lot of diving sub 200' in the Great Lakes and I never see anyone using less than 80% for their last gas. Most have 100%, the people using 80% are in the minority for sure.

 

[Tomeck]

I guess what I was asking is: why are you limiting yourself to two deco gases?

For 200 feet, one deco gase is enough. And for 330 feet, are two deco gases not enough? Three deco gases are not more easy?

 

[Doppler]

How many dives to 85 or 90 metres have you conducted?

 

[Tomeck]

How many dives to 85 or 90 metres have you conducted?

Never, my deepest dive is 75 meters.

 

[Tomeck]

Your bottom gas is wrong I would use 12/60 14 is way too high for 330'.

If I use 14% for 330 feet during 5 minutes, ppO2 is 1.54 and CNS is 5.2%, is CNS not too high?

 

[DeepSeaExplorer]

Just to entertain this conversation to see where it goes...

I would use 10/70 for bottom mix, with O2, 50% and 35% for deco gasses.

30/30 is not a deco gas and no one does a 300ft+ dive without O2.

 

[jtivat]

If I use 14% for 330 feet during 5 minutes, ppO2 is 1.54 and CNS is 5.2%, is CNS not too high?

I am not worried about my CNS clock I am worried about the 1.54 working PP. At 330' you don't have many options if you feel a tox coming on, at 20' on O2 I can take air breaks or if I feel funny I can go to a lower mix.