MOD Stickers

[PfcAJ]

Or if you use ideal mixes vice “Standard” mixes.

The only standard mixes I use are 50% and O2.

“Ideal” mix is a constant chase to shave off a minute or two of decompression and leads to all these (serious) problems we’re discussing right now.

 

[PfcAJ]

How is analyzing your gas before a dive an “additional variable”?

It’s not. Putting the wrong gas in the wrong tank and having to correct it with duct tape and magic markers is a variable, and one that doesn’t even need to exist.

 

[Jack Hammer]

I'm in the dedicated tank, tanks are cheap camp. I still remember starting out in tech diving though and needing sooo much new gear it seemed like a lot and an endless hole in my wallet... then I started knowing more tech divers and finding deals every where. I'll still occasionally repurpose a tank until I can pick up another dedicated cylinder if none are available, but I prefer to just grab a permanently marked one from a friend...

And always analyze, analyze, analyze... and if someone questions your tank contents, just analyze it again in front of them. Pride gets people just as dead as complacency does

 

[tomfcrist]

“Ideal” mix is a constant chase to shave off a minute or two of decompression and leads to all these (serious) problems we’re discussing right now.

No. It has merit in certain applications.

What leads to serious problems is being lazy and not analyzing your gas...because you “know” what’s in it. I had a guy lose his deco gas on an open ocean dive...the captain grabbed a deco bottle marked 70 and was going to take it down to him...the owner of said bottle stopped him and said it was O2 not 50%. Moral...just because you have dedicated tanks (and everyone else you dive with does) doesn’t mean you are immune to encountering stupidity and laziness.

It’s not. Putting the wrong gas in the wrong tank and having to correct it with duct tape and magic markers is a variable, and one that doesn’t even need to exist.

I agree. But it happens. People are stupid.

What isn’t a variable is putting whatever gas I want in a tank, analyzing it, marking it, marking the actual mod, and verifying all those things before I dive the tank. That should be SOP regardless of if the MOD marking is permenant.

 

[stuartv]

It’s not. Putting the wrong gas in the wrong tank and having to correct it with duct tape and magic markers is a variable, and one that doesn’t even need to exist.

It sounds like you're saying that having dedicated tanks and "only" ever putting the correct gas in that tank affords you the ability to not analyze your gas before you dive it.

I don't have dedicated tanks. I KNOW that I need to analyze the gas (and check the pressure) before the dive. I don't have any "peace of mind" coming from "reduced variables" that is encouraging me to cut corners.

It's not the "wrong" gas in the tank if the tank was never a tank dedicated to the "right" gas.

If you're going to cut corners, having dedicated tanks is not going to save your ass forever. If you don't cut corners, having dedicated tanks won't matter.

Regardless of all that, if I had the tanks and dedicated them to different mixes, I would still mark them with white tape and a Sharpie. I wouldn't be able to afford those fancy pre-printed MOD stickers after buying all those tanks... LOL

Oh, I just remembered another option. My tech instructor prints his own MOD stickers on a normal printer, with normal paper. Then, he cuts them down to size and puts them on his bottles with clear packing tape over them, to hold them on. I would do that before buying pre-printed stickers. He may or may not have dedicated bottles, but I believe he prints his MOD stickers that way because he fancies them up with some extra stuff like a custom font and some graphics related to where he went to college. He keeps extra printed copies of different MODs handy so he can easily change the label on a bottle if he needs to.

 

[tbone1004]

@stuartv it isn't an excuse to not analyze the tank. It's a historically deadly variable that can be minimized with a $150 max purchase for aluminum bottles.

Backgas is a bit different, but the difference there is no MOD stickers so you can't accidentally pick it up.

I print my own MOD stickers, but I thankfully have a big label printer that will print on vinyl so it works, but even still, you don't need preprinted MOD stickers from the scuba companies. Go old school and just grab the vinyl mailbox stickers from homedepot. $2 gets you a triple number set.

 

[RyanT]

I'm firmly in the camp of a dedicated tank for a particular gas. I always analyze my gas and have my buddy double check me as I'm doing it. I maintain this double check procedure because when I'm analyzing two or three different tanks, I could easily see myself accidentally affixing the analysis tape to the shoulder of the wrong tank. My buddy watches the analysis, and double checks to ensure that my analysis tape mix matches the permanent MOD number on the tank. If you swap your MOD numbers on the tank, then it simply introduces additional potential for error.

I use the mailbox stickers from home depot for my mod numbers.

 

[tomfcrist]

So you are saying that having a permanent MOD marked is less risk than putting the mod on every time you fill/analyze? This may be true, but in an imperfect world...people are stupid.

If I had to accidentally pick up a tank, I would trust the one with current dated analysis marked on it, and a matching Temporary MOD than a plain ole tank with 70 painted on it. Like I said before, I have seen idiots with bottles marked with one mod, but the gas don’t match. I don’t assume that I personally would ever be guilty of that, because I am OCD about my gear, and my checklists.

 

[UWZen]

Dedicated tanks isn’t an alternative to analysis after every fill before every dive. There’s still analysis tape sitting on the neck of the bottle with the date of analysis. But the dedicated bottle is just one more step in eliminating variables.

 

[tomfcrist]

Permenant markings make sense in certain circumstances...like the team concepts used by WKPP etc. you could be grabbing a stage that was placed in the cave by another team member a month ago. But it only has meaning if 1) there is a rigid QA process to document every tank has contents that match the permenant MOD...and 2) you actually trust the monkey that filled the tank and analyzed it.

If you use WKPP standard gasses, cool. I’m not hating on you. If you use something else... cool. Bottom line is that as long as you have a tried and tested method to ensure you have a proper mod on the tank, and actually follow a valid gas switching protocol to ensure you don’t switch to the wrong gas...you are going to be just fine.

Some folks will always claim that their way is “ the only safe way” or somehow superior to a different method, but they always fail to admit the giant holes in their method. The biggest hole is that people are stupid. Never underestimate your ability to **** up.