MOD Stickers

[Octopusprime]

I am new to technical diving and completed my first tec course and wanted to set up a dedicated Deco bottle or two with MOD stickers. I dive COLD Freshwater and if I'm going to travel to salt water I am not bringing tanks.

Where I am typical banked Nitrox is 32% O2 and if I'm going to run a Deco Bottle it will either be 40% or 50% O2, because of my training limits and if I'm going to have a dedicated O2 clean reg to do the 50% or not.

But to my question. The preprinted MOD stickers come in 20/70/120/190 ft stickers. It is obvious to me that the 100% O2 is the 20ft and the 50% O2 is 70ft but the rest seem a little arbitrary? 120ft would be 34% is that really a common blend? 190 ft is 24% why would anyone pay for custom fills for 24%. I feel like there should either be more standard stickers for 110ft and 130ft also.

If I'm going to use the banked nitrox it is likely going to be back gas which does not get labels, but if I was going to put in a stage I would need a 130ft sticker or would you just put the 120 stickers on it? I am feeling, for now, I should only label the 40 or 50% pony.

 

[JohnnyC]

Go here, in the dropdown options to order, it shows the available stickers and what their MOD's are. Example: 120 is 35/25, 190 is 21/35. They're GUE standard gasses.

Imperial MOD Cylinder Decals - Set of Two

 

[kelemvor]

Trimix.
Preprinted stickers come in a bigger variety than the ones you've listed. You might need to check more stores or just make your own. Light Monkey makes a variety. 20, 70, 120, 190, 240, 300, metric 6, 21,36,57,72,90. I'm sure there's more than just those in the world.

 

[tbone1004]

so remember that these are decompression mixes, so MOD is at 1.6, and that they are "roughly" 1.6. I.e. they are convenient depths, largely based on the caves they were standardized for and their MOD's may not be the "actual" depths. The mixes are set for He+EAN32, or for 35/25, He+EAN50

The deco gases are as follows
20'-O2
70'-50%
120'-35/25
190'-21/35

Backgases are here
100'-32%
190'-18/45
240'-16/60
300'-10/85

You can see with the 190' gas that there is a large discrepancy in the gas mix and that is due to the different ppO2's for working portions and non working portions.

In your situation, your EAN32 bottles should have 100' or 120' stickers on them. The WKPP standard is for bottom gas 32% bottles to have 100', and deco gas 32% bottles to have 120', but most of my buddies have 120' stickers on them.
Your "middle" deco bottle should keep a 70' sticker on there whether it has 40 or 50 in there, and then one dedicated for O2 with a OXYGEN-20 sticker on it

 

[boulderjohn]

As for me, I end up using some tanks for different purposes on different dives.

I have the preprinted labels for O2 and for 50%. For everything else I have white duct tape and a big, fat magic marker.

 

[divezonescuba]

Just in case someone has not seen this yet:

The blank "deco mix" stickers can be marked with a sharpie with the % and mod.

When the time comes, the sharpie markings can be easily disolved with a dry erase marker and wiped clean with a piece of paper towel or cloth.

 

[tbone1004]

@divezonescuba how often do you have deco mix bottles that are that far off from the standard gas bottles for it to be meaningful?

 

[PfcAJ]

Dedicate bottles to certain gases with permanent mod stickers.

Eliminate variables.

 

[divezonescuba]

Just gives more flexibility particularly for training with a limited number of cylinders and eliminates the duct tape.

We might use simulated gas content when practicing gas switch skills in shallow water during courses. The protocol is to have both the simulated percent and the actual percent marked on the tank at the same time. Then on the later dives in deep water just have the actual percent.

 

[tbone1004]

@divezonescuba care to give an example of that? also how are you that strapped for al80's and 40's?