Washington down at Blue Hole again, working on skills. Took my 2 tanks, as well as 2 rentals. The Friday refills were just fine. As usual, after the day'so dives, the DMs fill the rentals, as well as the tanks we leave down there. My LDS has a shed at the hotel, where we have a compressor and extra tanks.

Grabbed 2 of the tanks for today's dives, and already had my own, which were filled Friday night. Hooked up a rental this morning, and we were rushing, just slightly, to catch up with a buddy diving a specialty. Didn't sniff the tank when I put it on. Got in, and started right down.

The first breath told me something was wrong. It tasted almost like stinky rubber. Since I've never had a bad tank of air before, I didn't know precisely what I had, but strongly suspected. I wrote on my slate, telling my buddy. He took a breath, and agreed. Now, due to my flying days, I'm trained on how to recognize various symptoms from breathing  various airs. Told my buddy that we'd see how things went. My thought process was, I know how to recognize symptoms, but if one of the students got bad air, they might not, and things could go bad, quickly. 

After 7 minutes, I started to get a pretty good headache, let my buddy know, and aborted. Once out, and breathing fresh air, I started to get better. We didn't go beyond 39ft. I went to the 2 instructors and 2 Divemasters, and let them know, and to let the students know. One guy had a tank that had a slight smell, but nowhere as bad as mine. Didn't bother with the other rental that was filled yesterday, but went to my own 2, that had been filled on Friday. They were fine. Took a 2 hour SI, and was fine after that.

Lessons learned: even if a little rushed, don't skip steps. Would have only taken a second to know that I had bad air. I did realize that diving what I believed to be bad air was a risk, but given my experience, felt that it was an acceptable one, given concern that a student may not know what to recognize. My buddy kept eyes on me constantly, if anything had gotten beyond my control. We've dove a lot together, and I trust him implicitly. 

I'll be turning the tank in tomorrow, and the Course Director wants it analyzed. When I hear what the find, I'll post it hear. Since we stage 40 tanks down there, it's important to know if there is a problem, or just some person running their engine parked next to the shed.

Shit! That could have gone south badly! Glad you knew what to look for.

I always smell my air when I'm breathing off primary and octo when I'm setting my gear up.

I'm very interested to hear what the analysis results are.

Honestly, you should have called the dive right away instead of trying to tough it out. There isn't anything down there worth it.

Taking a carbon Monoxide/Dioxide hit isn't something you want to happen at depth. One of our locals around here took a CO2 hit a few weeks ago several thousand back. His team put him on his bailout gas and scootered him back to the surface. He said the only thing he remember of the entire dive was basically waking up at 20 feet on his deco tank which was 100% O2.

You make a good point, Jerr, but like I said, I felt it was a reasonable risk, didn't go deep, and was being constantly monitored. It's not something that I'll ever do again. Glad that your guy was safely bailed out.

We will have to agree to disagree. That was not a reasonable risk to take IMO. I'm not trying to be condescending or disrespectful but we all learn from others. You contradict yourself a bit calling it a reasonable risk but then you say you will never do it again.

I am curious as to how your other DMs and students perceived this. You just showed some students that its okay to continue a dive for a little bit with suspected bad gas. I know you were trained to immediately abort a dive. Why in this instance did you deviate from that training?

I am far from a scuba nazi but I really do feel you made the wrong call here.

Gotta agree here. No dive is worth the few minutes to change tanks.
It's also why we have a culture of never giving anyone shit for calling a dive.

I didn't actually have any students. My buddy and I were fun diving, while the shop had students.
I felt that the risk was worth learning from, and since I did, I will never do it again. I accept fully that I screwed up completely by not checking my tank when I was putting my gear together. I make a point to learn from my mistakes, and getting a bad tank has taught me that yes, it is an important step in putting your gear together. I can also, once I am a certified instructor, use this as the perfect reason when teaching students.
Perhaps I am looking at the risk in the wrong manner, and I can fully accept that I made the wrong call. Not the first time, and I can learn from that as well.

I am just concerned with the process that you used to come to that decision to continue diving. Unless I misread your post, students still saw and heard about what happened and your decision to continue diving until you started getting headaches.

I honestly think that someone that is wanting to become and instructor should have better decision making skills. Its not just your life that you have in your hands while being an instructor.

I am really glad that you learned something from this experience but the fact that you had this "wait and see" mentality really bothers me. That kind of thing kills and kills quickly and without discrimination. You can skip every setup step there is and it shouldn't affect at all the decision process to abort a dive. What caused a problem and what you do to correct that problem don't really have anything to do with each other. I don't have an issue with your failure to catch the bad gas as much as the decision to continue diving once you figured out you did have a gas problem.

This is the same reason why I posted in another thread that I have no interest in becoming an instructor. Just being "lead diver" on tech dives every now and then is enough to make your skin crawl.

I'm just gonna come and say that what you did was plain fucking dumb- for any level of scuba certification.

ANYTIME there's any kind of taint to your gas mix, whether it is air, nitrox or trimix, it is cause to abort the dive- not experiment and see how it feels.

Do you have any idea what the partial pressures of the unknown gas mix were and how it could have affected you? You could have very easily passed out underwater, leaving your buddy to do a no-shit unconscious diver rescue for your very dumb ass.

I hope this pisses you off, because the painful lessons are the ones that stick.

In full disclosure: I did the same dumb fucking stunt 35 years ago- and damn near died because of it.

I don't care to beat up the OP for reporting & sharing this.  


OP: Have you also contacted DAN to share your near miss?


OP: Near Miss learn from it, and you are still around to learn from it.


Its funny how we talk ourselves INTO something when we are there, but, afterwards say NEVER EVER-ER AGAIN.


Some of the symptoms of CO poisoning are anxiousness or calmness and a bit of confusion.  Hence, why I suspect you also talked yourself into continuing the dive.



Thanks for sharing, glad it resolved well.


As a side note: CO poisoning will register as 100% perfusion with a pulse oximeter, don't rely on an oximeter to diagnose CO poisoning.

The antidote is as pure of oxygen that can be delivered and monitor the person in case of collapse-unconsciousness.

CO poisoning is SERIOUS and should be treated IMMEDIATELY as its life threatening.

There was a boating death in North Carolina recently: NEWS STORY

ALWAYS analyze EVERY tank for O2 and CO.

Buy a Cootwo or a separate CO analyzer if you have to. It's not worth the risk to save a couple hundred bucks that will pay for itself the first time you get bad gas.