Diluent MOD

[Capt Morgan]

I was wondering what PO2 people base the diluent MOD on ?
I'm asking from a cylinder depth marking point of view.

[dwhitlow]

interesting question with 2 answers. However, I never mark the MOD on my diluent I merely mark the contents.

If I did the MOD would be based on 1.6 as that reflects the suitability of the gas for OC use, which might the case if you bailed out.

However, suitability for diluent is somewhat different and higher than 1.2 might give you challenge to flush down the loop ppo2.

[Barrygoss]

I was wondering what PO2 people base the diluent MOD on ?
I'm asking from a cylinder depth marking point of view.

Dil cylinder is for my use only. Contents are marked, but as I'll not be switching to it at some point in the dive, no point in marking the MOD, as it's good for the dive.

B

[Capt Morgan]

Likewise Dave I never mark my cylinders with MOD but I was wondering what others based it on.
I always have my BOV connected to my deep BO tank so I know what I base it on.
When the CNS clock might be an issue I would run my unit at 1.2 so I like to have a po2 of around
1 - 1.1 bar but when CNS isn't an issue I run a sp of 1.3 and would be happy enough with an MOD
based on 1.2
It's not a game changer but I would just like to know what others think.

[Capt Morgan]

Dil cylinder is for my use only. Contents are marked, but as I'll not be switching to it at some point in the dive, no point in marking the MOD, as it's good for the dive.

B

But what are you basing the fact that it is good for the dive on ?
Do you see the MOD as dynamic ?

[JPTaylor]

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[Barrygoss]

But what are you basing the fact that it is good for the dive on ?
Do you see the MOD as dynamic ?

Dil is the 3 or 5 mounted to the unit, usually 15/55, and marked as such, hence it'll be good to use throughout the dive (or I'll use a different dil, I'm currently looking at 10/60 for a dive)
But I think you're thinking of deep bail, that's normally the same as dil for me, and again it's not marked as its plumbed into the unit using a QC6, should someone else need it at depth, it's a matter of disconnecting the QC6 and passing over the whole cylinder, takes about 10 seconds.
I don't see the need to mark a MOD on a cylinder that is good for the max depth of the dive I'm doing?

B

[JPTaylor]

deleted

[Capt Morgan]

Dil is the 3 or 5 mounted to the unit, usually 15/55, and marked as such, hence it'll be good to use throughout the dive (or I'll use a different dil, I'm currently looking at 10/60 for a dive)
But I think you're thinking of deep bail, that's normally the same as dil for me, and again it's not marked as its plumbed into the unit using a QC6, should someone else need it at depth, it's a matter of disconnecting the QC6 and passing over the whole cylinder, takes about 10 seconds.
I don't see the need to mark a MOD on a cylinder that is good for the max depth of the dive I'm doing?

B

No I'm interested what people think about Dil MOD

[Barrygoss]

It's for when your pulling a cylinder out of your dive store to prep your unit...

I only dive 15/55 as dil. That's the only trimix in my garage (so far, as its good to 90)
Dil cylinders have 15/55 in them.
This weekends 45m max dives were on 15/55, so I did a bit more deco.

Having cylinders of dil in the garage with different MOD's is a mistake waiting to happen. (Me being risk adverse)

And with only 3 gasses in my garage I have managed to fill my O2 with dil once already in 7 years of mix diving. (As I couldn't get the unit to read 0.9 before the dive, I bailed the dive)

B

[Vanny]

It's late and I'm working , but 15/55 good to 90? Is that metres ?? OC or CC Surely that's too rich ?

[dwhitlow]

It's late and I'm working , but 15/55 good to 90? Is that metres ?? OC or CC Surely that's too rich ?

yep, too rich for 90

[Vanny]

Must be a typo or he's on the sauce.

My dil Max's out at 1. Don't mind a bit less. Wouldn't put MOD on , it's hidden in a plastic box.

[Barrygoss]

Diluent MOD

yep, too rich for 90

And that depends on what you want a dil flush to do.
15/55 is has a mod of 97m so at 90 would flush to 1.5. A nice round figure for cell verification.
I dive MCCR, as does Morgan, I'm not looking to drive the PO2 down fast because the solenoid has tried to kill me. I'm looking to verify cells that may be a bit "funny"

I won't have had an O2 spike that might be up in the 2.0's and need the emergency crash that the low O2 dil has. Just another thing to consider.

B

[dwhitlow]

And that depends on what you want a dil flush to do.

I don't want to dil flush as that uses dil! I might need that!

15/55 is has a mod of 97m so at 90 would flush to 1.5. A nice round figure for cell verification.
I dive MCCR, as does Morgan, I'm not looking to drive the PO2 down fast because the solenoid has tried to kill me. I'm looking to verify cells that may be a bit "funny"

different units different priorities

I won't have had an O2 spike that might be up in the 2.0's and need the emergency crash that the low O2 dil has. Just another thing to consider.

scooting down the shotline has interesting consequences, whatever you are diving, but is so civilised