They're filled with Air, I did it on my compressor at home.

[skip]

Three of us were diving a local quarry...I know it's not a cave...bear with me. As we are gearing up for side mount with deco, I turn and say we need to analyze our tanks and check each other. My buddy says we don't need to do his, cause he knows they are air cause he filled them himself from his home compressor.

Naturally, I relate the story of the recent death and say I cannot do a "trust-my-ass-to-your-gas" dive unless I see the analysis myself. My other buddy and I are diving air also, but I topped off nitrox with air and wanted to verify my analysis and my other buddy had also topped a set of tanks off with air and had not analyzed them at the shop - not analyzed them at all yet.

I had 23% as I expected. My other buddy had 21% (never had nitrox in them). My buddy, the one who filled his own with air at home...had 33.5%. WTF??

"Oh, I forgot, I took these to cave country awhile back and they had left over nitrox in them. I guess I just topped them off with air at home."

HOLY CARLOS!

Our planned depth was 125 feet. Only a 1.6 PPO2, but still.... we are doing reverse profile repetitive deep dives to 150 feet (using helitrox for the deeper dives) over two days and starting off with inaccurate information would only domino into disaster ... maybe.

We then analyzed the deco bottles, all well. We then checked all tanks for CO, all well.

We then went diving, did two dives instead of three and called it day.

I have trusted my buddy many previous dives with having the right mix based on his say-so, and probably would have again if not for Carlos.

So I'd like to say thank you to Carlos. I am very sorry he is dead, but I can vouch for at least one person who has taken it to heart and changed their practices. And has passed it on to two others.

skip

[Mark Vlahos]

Bingo!

[hunabku]

Katie and I checked together today at the dive site as well. We normally do, it just sinks in a little more now.

God job you made it a point.

[LCF]

Great post, great story.

[kwinter]

Putting a bad situation to good use is what these forums should be all about. Bravo Skip. Glad it worked out well. And glad you did the CO analysis too. I hope your buddy learned a valuable lesson.

[FW]

...I had 23% as I expected. My other buddy had 21% (never had nitrox in them). My buddy, the one who filled his own with air at home...had 33.5%. WTF??

"Oh, I forgot, I took these to cave country awhile back and they had left over nitrox in them. I guess I just topped them off with air at home."...

What mix did he have in FL, that would be over 32% after being topped with air? BTW, good catch!

[Jim Wyatt]

Skip--Was the bottle marked? Is it possible he had EAN50 from deco on a deep dive, then topped it with air?

[FW]

All this has made me a little more careful too. I was doing a sump dive in PA last weekend, that was in a cave with a 58 deg dip. There was a possibility the sump would continue at 58 deg, and get deep, so I grabbed my set of tanks with "air" in them. Just because of Carlos' accident, we went ahead and analyzed them. The first one was 21%, the second one was 79%. I had even put tape on it, with 80%, but never thought to look for it, since I was so sure they were both air. I had loaned one to someone to use as a deco bottle, and and forgot about it, then I topped it with air. My buddy didn't like the look of the sump, so he loaned me his air filled tanks, after re-analyzing them as well.

Since I stated telling the story, I will finish it. After dragging gear through the cave, the sump had an exit the size of a basketball hoop, so I turned the dive at 6' penetration.

[powerglider]

I don't have any questions for you, I'm just glad everyone is OK. Great post!

[skip]

I don't know what he was doing with such an odd mix. He has 4 sets of 104's set up for side mount and they were all out of viz and/or hydro except the one set, so that was the set he brought with him this trip. He also dives a local deepish quarry where 36% is used and I suspect that was really where he got the mix, rather than cave country. We do use EAN50, but in AL80's, so I doubt that was it. He also has a whip and will whip gasses between tanks; so that too is a possibility. The tank had no label, was vizzed for air, not nitrox. I have no idea how he keeps track of what mix is in which of his many tanks, although when we dive together I pull out the duct tape and sharpie. Plus he loans his tanks to buddies fairly frequently so that's another possibility. We didn't spend any time trying to figure out how the mix got in them, we just adjusted our dive plan and went diving!

Dang Forrest, not you too! All this makes me wonder how many of us have dove with tanks with mistaken mixes - "knowing" what we were breathing and being wrong. It may occur more than we think and may indicate that Carlos' error may be more common in the community than we like to think. Carlo's paid the ultimate price, but how many have dove the 80% mix, not encountered deep cave, and lived never realizing what might have happened? Scary stuff.

Dang. Not only am I more vigilant on gas analysis, it's made me review my practices in general and back off an aggressive dives as well. Not just Carlo's but the solo cave diver with the heebie-jeebies. Thanks to both, and to the posts about both.

skip