Is dive certification really necessary?

[BRT]

Remember I said he labeled them wrong.

My HP100's were about half full of 36% when I dropped them off. They only banked 30, so I told him that was fine. He filled them with 30% and wrote 30% on the yellow tape. I suppose his theory was that if he put 30% in a cylinder, it must be full of 30%? They didn't have a nitrox log so we just took the tanks and on the boat I plugged my analyzer in just because.... 33%.

On the shallow reefs we were diving that day it didn't really matter, but it's the idea that it was labeled wrong. And that's why you always check your own cylinders. That's why I found it kinda silly that he was being such a snob over a nitrox decal. I've had no fill station training so I don't know the procedure, but I do know around here, the guy fills the tank, he analyzes it, then when you pick it up you analyze it and sign the log. Unless it's a hot fill while you wait, then you watch him analyze it and see the readout so there's no need to analyze it again.

I analyze the mix going into the compressor, analyze the mix coming out. Then analyze the full tanks. If I am diving them right away I trust that. I put the date and the mix and the MOD on painters tape. If there is a delay in breathing them I check them again.

 

[Anthony in NC]

I analyze the mix going into the compressor, analyze the mix coming out. Then analyze the full tanks. If I am diving them right away I trust that. I put the date and the mix and the MOD on painters tape. If there is a delay in breathing them I check them again.

If I have 32% in a cylinder and it sits for 6 months, what percent is it gonna analyze then, assuming all the other factors like analyzer accuracy are the same?

I can see a 1% variance maybe the calibration difference in my analyzer and his. But I don't think it was coincidence that his analyzer just happened to be 3~4% off and the error just happened to be what I told him to put in them. He just filled them and didn't analyze them.

I know what he did. He slapped them on the whip and didn't drain them prior to filling them. That's why the mix fell between 30 & 36%. I have no fill station training, but I'm pretty sure you can't get 33% from 30%.

Thats like asking for change for a dollar and getting $1.25 in change back.

 

[Celt]

Then just call me dumb enough. By the time I was 24 I had the equipment, the compressor and the boat but no certification.

Same here, and I was getting paid 5 times what I would on land. The only questions I was ever asked is “can you do the job” and when?

 

[boulderjohn]

If I have 32% in a cylinder and it sits for 6 months, what percent is it gonna analyze then, assuming all the other factors like analyzer accuracy are the same?

Good question. In my case, I question my memory--did I update that sticker when I put the tank away, as I am supposed to? I have made enough personal mistakes in my life to doubt my memory on pretty much everything.

Here are two stories to illustrate.

The diver had his own compressor and did his own fills at home. He was diving at Ginnie Springs in Florida, with a continual depth in the 100 foot range. He was planning to use a stage bottle that clearly said "oxygen" on the outside. Friends asked him about that, and he said that he had just not bothered to change that label--that tank just had air. He had filled it himself, so he knew damned well what was in it. When friends insisted he analyze, he got angry, so they backed down. After he died, the analysis of the tank showed it did indeed have pure oxygen.

The diver was preparing for a dive using his doubles, and he had an accident that broke his foot. He could not dive for months. When he could finally dive again, he booked a trip on the Hydro Atlantic, a wreck with a depth range of 150-170 feet. He remembered clearly that his doubles had air in them, so there was no need to analyze. After about 20 minutes on the wreck, he suddenly made a rapid ascent, which is actually what killed him. The rapid ascent was probably because he felt signs of toxicity. His tanks analyzed at 36%.

 

[Eric Sedletzky]

Remember I said he labeled them wrong.

My HP100's were about half full of 36% when I dropped them off. They only banked 30, so I told him that was fine. He filled them with 30% and wrote 30% on the yellow tape. I suppose his theory was that if he put 30% in a cylinder, it must be full of 30%? They didn't have a nitrox log so we just took the tanks and on the boat I plugged my analyzer in just because.... 33%.

On the shallow reefs we were diving that day it didn't really matter, but it's the idea that it was labeled wrong. And that's why you always check your own cylinders. That's why I found it kinda silly that he was being such a snob over a nitrox decal. I've had no fill station training so I don't know the procedure, but I do know around here, the guy fills the tank, he analyzes it, then when you pick it up you analyze it and sign the log. Unless it's a hot fill while you wait, then you watch him analyze it and see the readout so there's no need to analyze it again.

I was taught that if you’re going to get into nitrox then it is best to always have your own analyzer. You can watch a guy do a hot fill and watch him analyze it but how do you know if his analyzer is off? Two checks with two different analyzers is better than one.

 

[BRT]

If I have 32% in a cylinder and it sits for 6 months, what percent is it gonna analyze then, assuming all the other factors like analyzer accuracy are the same?

I can see a 1% variance maybe the calibration difference in my analyzer and his. But I don't think it was coincidence that his analyzer just happened to be 3~4% off and the error just happened to be what I told him to put in them. He just filled them and didn't analyze them.

I know what he did. He slapped them on the whip and didn't drain them prior to filling them. That's why the mix fell between 30 & 36%. I have no fill station training, but I'm pretty sure you can't get 33% from 30%.

Thats like asking for change for a dollar and getting $1.25 in change back.

It's not gonna change. But I still test if the tag is old.

 

[EFX]

The diver was preparing for a dive using his doubles, and he had an accident that broke his foot. He could not dive for months. When he could finally dive again, he booked a trip on the Hydro Atlantic, a wreck with a depth range of 150-170 feet. He remembered clearly that his doubles had air in them, so there was no need to analyze. After about 20 minutes on the wreck, he suddenly made a rapid ascent, which is actually what killed him. The rapid ascent was probably because he felt signs of toxicity. His tanks analyzed at 36%.

In regards to the signs I always believed that oxygen toxicity comes on suddenly. What are the signs and how long do you have before trouble sets in? Is it possible to avoid a toxic episode by going shallower when the signs first appear?

 

[boulderjohn]

In regards to the signs I always believed that oxygen toxicity comes on suddenly. What are the signs and how long do you have before trouble sets in? Is it possible to avoid a toxic episode by going shallower when the signs first appear?

VENTID

Visual disturbances
Ear ringing
Nausea
Twitching,
Irritability
Dizziness

Some people add "Con" to the VENTID list for convulsions, but I figure going into convulsions is not a valuable warning sign.

I have heard of a number of cases of people blacking out on deep dives, and I have always wondered about simple unconsciousness as a result. Of course, blacking out is not a valuable warning sign, either.

 

[MichaelMc]

with James playing the straight comedian while usually using carefully worded opinions and stories, and then Brando is....welll the opposite.

They have some interesting stuff, but the signal to noise ratio could be improved.

@boulderjohn, that lead-in, to getting to the point, was longer than usual. Start listening at 14:11 with 'So as I was saying, I got on the board ...'. They miss a few points but it was a good conversation, and both of them stay on the topic, once the lead-in is done.

 

[ABK]

TGDP is like a fine Bourbon. It's an acquired taste.
The guys are pretty funny but more importantly they're saying what needs to be said about the industry. "Speaking truth to power" as liberals like to say.
In regards to the question at hand, I think this thread is asking the wrong question. Instead of asking "is certification really necessary?" we should be asking why that's even questionable.
It's questionable and debatable only because of the serious lack of quality instruction out there.