Permanent MOD markings on tanks

[cavediver256]

.............intellectually lazy and gets us no where.

Well I would think "intellecutally lazy" is the reason for this thread if nothing else........

[Kelly Jessop]

I'd like to say 'no, they shouldn't', but I also understand that people make mistakes. Everyone does. Understanding that people do and will continue to make mistakes reinforces the need to be vigilant and remind each other to slow down and go through the steps/process. Think, for a second, of how the last few 'wrong gas' fatalities happened. Not following the procedure. Something so simple, yet it has cost how many lives?

A 'screw it, let darwin sort it out' mentality is sloppy, intellectually lazy and gets us no where.

You are right,the human factor is huge. Testing gas,marking tanks,and in water verifying that you have the correct tank are all essential,but somehow this slips by us and the results are costly. It really sucks that accidents make us more vigilent in something that there should never be a shortcut. Maybe the buddy system needs to be extended to testing each other's tanks to verify things? I know some guides who will test the person they are taking tanks,maybe it is worthwhile to save the sad job of pulling a buddies body out of the cave.

[jcr]

But back to my initial question... I am glad that some local divers have dozen of tanks and are well disciplined to manage their tanks... but is this rigorous enough that we could rely on permanent markings on any cylinder? I don't believe so... and I think permanent markings on tanks that are not self managed may not be helpful at all.

I'm not sure I understand what you mean by "manage their tanks." The entire point of MOD markings is to rely on them and them only in the water. The analysis before the dive verifies that the contents match the MOD markings and that it can be relied on. That's the system. It makes no difference whether they are your tanks or not.

[kwinter]

I guess I'm the only one who also labels his second stages. All bailout cylinders have small tags at the second stage as well as the QD with the mix. I try to position them so they stick up right in front of my eyes and I see the mix before I stick it in my mouth. Yes, it has the potential to be mislabeled, but that's why I am meticulous about it.

.
I can't imagine that a technical or cave diver would not have the tanks needed to do the planned dive, would not have analyzed the tanks just prior to the dive, no matter what markings are on it, or would rent tanks and not analyze them and mark accordingly.

Then you have no imagination.

[Anders Knudsen]

Hi all,

I think it is a great thing, that we all try to make diving safer and discuss these accidents in order to learn from them.

I dont believe that this is solely to do with cylinder markings though.
I am in general a firm believer of dedicated tanks - and i do have fixed MOD's on all my deco and stage cylinders ( MOD stickers at the sides near the bottom and permanent markers 4 times around the cylinder neck ) but this is just how I do it - I think there are many ways that would work, and when I travel I am perfectly happy using differnt methods. One thing i would never skip is my personal analyses marking at the neck of the tank! a peace of duct tape with the date of the analyses, the exact content and MY signature. If a tank for some reason dont have this information, i dont breath it!

But what is even more important than the cylinder markings ( as long as they are marked ) is the switching procedure! and that our buddy confirms the switch! I know a lot of us says, of cause! we always do this - but it would have saved Jim and probably also the Ginnie accident, and most other switching accidents!.

What I learned from this accident ( the way i think it happened ) is that this could just as well have happened to me! I am extremely anal about switches under water, really check and re-check switches. make the entire team check EVERY single cylinder drop - is it the right cylinder? is is closed ? so you know what your team mate is breathing and have on him at every single point of the dive.

BUT I can imagine not being as anal about the starting stage, we are all good divers, in a place with multiple tanks and scooters - and we are on the surface! who makes a mistake here ? sure we check and make sure, but not as through as at the other stages at the dive - i guess we dont expect an error on this stage of the dive, we are eager to get going, and truth be told often it is pretty uncomftable being to long on the surface with tons of cylinders and multiple scooters, so everybody is fairly eager to hit the trigger, and our procedures are made in a world of no gravity! some of them are pretty hard to do at the surface.

But imagine - you are a good diver!, you are going to do whatever major dive, maybe even an exploration dive.
You are at the surface, loaded with gear laughing with your team joking of how much line you are going to add, and you know - that it requires all your focus to get to the end of line with enough gas to actually explore for a while. your focus is at the goal not on the travel there.
you pull the wrong reg from the stack of cylinders, but it is hard to see from pile of cylinders under your arm, and you just managed to clip everything on - it is 40 deg and you are a bit warm.
you yell at your buddy to see if he is ready, and with a laugh he gives you the 1-2-3- GOGOGO and you hit the trigger !and you never look back before you tox

this shouldent happen! we all know that it should not, and that we should have caught it ourself and our buddy should have caught it - but i could so see the scenario happen.

The dive starts and ends at the surface! I for now will be way more anal about my "surface switch" from now on - this is a dangerous one, as I am actually carrying oxygen during this switch!

[Anders Knudsen]

ok and I have now learned that this has nothing to do with the current devils cave accident, I am sorry for speculation! and acting without correct information the rest of my post i think still makes sense though

[mtherr]

I started this thread after reading a comment to the effect that permament marking was important and temporary markings were a bad practice. My reaction to this comment was negative because I am pretty sure that permament markings are not universally respected. This thread has nothing to do with the Accident analysis discussion.

I understand that some participants really dedicate tanks for mixes and this is good. I did the same way before it became a practice to mark tanks with numbers (I used -- in mid 90's -- to have a Yellow tank with yellow face Jetstream for EAN 32 deco mix, Red tank with black Jetstream for EAN 50 deco mix and green O2 marked with green hose and green taped Sherwood second stage for O2). My back gas was accessed with Scubapro regs. I would never mix these things up when I was doing that.

However, this works when you have your own stuff, you controll it and others are not using it. This practice was also capital in ensuring safety for the WKPP project, I am sure.

But as a user of temporary tanks while travelling, permament markings have no meaning to me. I rely to in shop and on site analyzes. Temporary markings are used to make sure I dive with the tanks I analyzed on Carabean trips. While I used to do more complex dives when I was younger, my dives now are pretty much all single-mix nitrox dives with O2 decompression.

Thanks all for partiipating and I would like more discussion around how to ensure proper permanent marking or how to disable it if not reliable (for example, should I put a cover on marked tanks when I rent a tank while travelling)?

[gianaameri]

I started this thread after reading a comment to the effect that permament marking was important and temporary markings were a bad practice. My reaction to this comment was negative because I am pretty sure that permament markings are not universally respected. This thread has nothing to do with the Accident analysis discussion.

I understand that some participants really dedicate tanks for mixes and this is good. I did the same way before it became a practice to mark tanks with numbers (I used -- in mid 90's -- to have a Yellow tank with yellow face Jetstream for EAN 32 deco mix, Red tank with black Jetstream for EAN 50 deco mix and green O2 marked with green hose and green taped Sherwood second stage for O2). My back gas was accessed with Scubapro regs. I would never mix these things up when I was doing that.

However, this works when you have your own stuff, you controll it and others are not using it. This practice was also capital in ensuring safety for the WKPP project, I am sure.

But as a user of temporary tanks while travelling, permament markings have no meaning to me. I rely to in shop and on site analyzes. Temporary markings are used to make sure I dive with the tanks I analyzed on Carabean trips. While I used to do more complex dives when I was younger, my dives now are pretty much all single-mix nitrox dives with O2 decompression.

Thanks all for partiipating and I would like more discussion around how to ensure proper permanent marking or how to disable it if not reliable (for example, should I put a cover on marked tanks when I rent a tank while travelling)?

Allow me to help then.

WKPP (and DIR, GUE, TDI, IANTD, IART... apologies if I forgot to include the rest) got it wrong.

SCUBA cylinders, rentals or personal, should bear no gas markings and no stickers whatsoever to start.

The diver analyses the gas and with a permanent marker places on the tank neck his name and the MOD (meaning the diver chosen gas switch depth) of the gas mix.

So, for example, Carlos (a hypothetical diver) buys a new Alu80 cylinder and then he fills it with O2.

He then analyses and writes on the neck with a black permanent marker "Carlos" and "6M" (or "10F" if feet he uses as unit of measurement).

Weeks later he decides to use Air instead of O2.

He takes his Alu80 tank and wipes off with a bit of solvent the "6M" and empties the tank and fills it with Air.

Then Carlos analyses his tank to confirm it contains Air and marks it "66M" (the name "Carlos" is still there, so no change there).

When Carlos returns from his dive - having breathed Air and not O2 - he stores his tanks in the garage.

Next time Carlos picks the tank up, he repeats the process and before the Alu80 leaves the garage he makes sure the tank is analysed and the correct MOD is permanently placed on the tank neck.

Unfortunately, somebody a long time ago decided to do it differently, and then somebody else decided to do it a little more differently as well, and where we are now is tanks with far too much information and stickers of all kinds when all we need on the tank is 2 pieces of information: name and MOD.

[jj1987]

Allow me to help then.

WKPP (and DIR, GUE, TDI, IANTD, IART... apologies if I forgot to include the rest) got it wrong.

SCUBA cylinders, rentals or personal, should bear no gas markings and no stickers whatsoever to start.

The diver analyses the gas and with a permanent marker places on the tank neck his name and the MOD (meaning the diver chosen gas switch depth) of the gas mix.

So, for example, Carlos (a hypothetical diver) buys a new Alu80 cylinder and then he fills it with O2.

He then analyses and writes on the neck with a black permanent marker "Carlos" and "6M" (or "10F" if feet he uses as unit of measurement).

Weeks later he decides to use Air instead of O2.

He takes his Alu80 tank and wipes off with a bit of solvent the "6M" and empties the tank and fills it with Air.

Then Carlos analyses his tank to confirm it contains Air and marks it "66M" (the name "Carlos" is still there, so no change there).

When Carlos returns from his dive - having breathed Air and not O2 - he stores his tanks in the garage.

Next time Carlos picks the tank up, he repeats the process and before the Alu80 leaves the garage he makes sure the tank is analysed and the correct MOD is permanently placed on the tank neck.

Unfortunately, somebody a long time ago decided to do it differently, and then somebody else decided to do it a little more differently as well, and where we are now is tanks with far too much information and stickers of all kinds when all we need on the tank is 2 pieces of information: name and MOD.

Mod stickers also tell the tank monkey what mix should be in there. Not to mention their obvious use of showing a buddy what you are breathing (which worked in Carlos' case, but was ignored).

I have no issue using tape to cover the 9 and writing a big fat 5 in it if I'm going to Indian and putting 150 gas in a 190 bottle. Just whatever you do, fix or cover the mod before filling.

When you get filled, tape the valve off after analysis. If there's no tape, recheck your gas.

[gianaameri]

Mod stickers also tell the tank monkey what mix should be in there. Not to mention their obvious use of showing a buddy what you are breathing (which worked in Carlos' case, but was ignored).

I have no issue using tape to cover the 9 and writing a big fat 5 in it if I'm going to Indian and putting 150 gas in a 190 bottle. Just whatever you do, fix or cover the mod before filling.

When you get filled, tape the valve off after analysis. If there's no tape, recheck your gas.

I put the analyser at the base of the tank if the tank needs analysing, so when I pick the tank up I can see the analyser and remember to use it.

I do not agree though on the "theories" (i.e. DIR...) whereby the onus is placed on the buddy to verify the gas the other diver is using.

The decision to dive is of one person only - the diver.

The stuff which goes in the mouth is for one person to decide and put it in the mouth - the diver.

If my buddy breathes O2 instead of 12/88 - he made a mistake and it has got nothing to do with me. Same if I were to make that mistake - it is my responsibility to make sure that what I put in my mouth is good for me.

So, in the case of Carlos (the hypothetical diver I made up in this thread), if he is my buddy and puts in his mouth an O2 reg instead of an Air reg - his mistake and no moral responsibility on my part. I have to worry already about what reg I am putting in my mouth, that I should not have the additional task loading to check/baby-sit everybody else.

Now, I see all the times people strapping on 3 tanks and putting behind and around their neck 3 hose and 3 regulators and I wonder - how the hell this guy does not make a mistake and take the wrong reg? (if he does, his problem for sure).

So, what I do, because I make all sorts of mistakes, like forgetting to put my fins ON and start the dive with no fins (fully loaded with 4 tanks, a rebreather, a scooter, and a back-up scooter...), I put a woman's short nylon sock on the O2 2nd stage.

It protects it, and if I put the O2 reg in my mouth by mistake it will feel "different."