Am I paranoid to consider analyzing recreational air?

[dive_turkey]

Glad to hear you're taking action! I've been reading quite a bit on the skill of influence (I'm in my final year of a degree in Leadership & Workforce Development), and it turns out that quite often a group of people will all be sitting around having the exact same idea, but it's that one person who speaks up that initiates the change! People will often not speak up because try are worried about being embarrassed, ridiculed, or sometimes that it's simply not their place (like correcting another person's child). That's one thing I've really learned to enjoy about the diving community, which is that it's ok to ask speak up and ask questions. Sometimes people will be a little frank or abrupt with you, but at least you know they're listening and concerned. Divers are very protective of their sport and understand that a diving fatalities actually have second and third order effects on us all.

Good luck with your CO detector!

 

[drbill]

I've never analyzed a tank in over 50 years of diving (I don't use geezer gas... not old enough yet). One shop here fills air only, the other shop I use fills Nitrox and oxygen but using a totally separate system. I'm not suggesting people shouldn't analyze, just that I don't feel the need to at this point.

 

[Chilly_Dipper]

On my rebreather we replace O2 sensors after 1 year. Given $80/sensor/year, what is that like 16 coffees?

---------- Post added September 9th, 2013 at 12:27 AM ----------
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So Meg rebreathers have a minimum of 3 sensors (to the best of my knowledge) so that's $240 per change. They also degrade faster with use I have friends that change them every 3 months due to their heavy dive schedules.

 

[Pelonofear]

During my recent certification in Stress + Rescue the subject of CO contamination came up, and I realized I had never really thought about it. Needless to say, now I am quite (maybe overly) conscious, especially after reading about accidents and the like. Could anyone recommend a CO analyzer? I guess it is super expensive, but maybe it is something worth it to look for (or at least start to consider)?

 

[dive_turkey]

Hence my point. I've always been a safety oriented guy, and while my experience in diving may be low for a guy certified in 1993, my experience in procedure, safety, and redundancy is not. This is why I brought it up.

 

[Pelonofear]

I could not agree more, and was very pleased when I found your thread. And by the way I relate a lot with you. I got my certification in '93 as well while very young, but stopped mainly due to University, PhD etc... and no money. I finally got back into diving just a couple of years ago.

 

[dive_turkey]

Well alright then! Also, welcome to the forum! I'm pleased to see I've drawn in only your fourth post, as well as your superior dive experience at 50-99. I can't wait to move to the 25+ category myself.

In all seriousness though. Diving has changed since I first learned about it. I've been reading many of the books out there as well, such as Diver Down, Last Dive, and recently, Fatally Flawed. I strongly recommend all three books for someone just reintegrating back into the scuba world, especially the first title.

I love that I can still contact my first Dive Instructor, as she has and continues to be a close family friend. That has also helped my reintroduction to a childhood fascination. I hope that you can reconnect to your original motivation as well, as that has been a driving force in motivation to seek out opportunities for education and experiences. I have found that the forums (which did not exists when I started diving) have proven to be very helpful!

Anyway, I'm trying not to hijack my own thread. I hope you gain something from this one, as well as the rest of the community. I should suggest that we continue on the subject of analyzing our tanks prior to breathing from them!

 

[MalibuJerry]

It seems to me that if you are getting your air fills from a store that does not do nitrox, it is highly unlikely that you will have any other mix. However there have been enough incidents with CO in the mix that I am going to now purchase a CO analyzer. Previously I asked to see the compressor and tried to judge the likelihood of a mix with CO by the setup, but now I'm not so sure that is the best way. I have tanks that I use for Nitrox and Trimix and I never breathe off of them without analyzing them the day of the dive or the night before and labeling the bottles, even if I did the fill and even if I know it is air in the bottles.

But it seems unlikely that a store would be giving you a bottle with nitrox in an air bottle if they do partial pressure blending. For stores that do nitrox with a membrane system, I would guess that they are doing 28%, 30% or 32%, so you should be fine with any recreational dive if there were to be a mistake and you were diving air tables (computer). The worst case would be 32% at 130 ft which would give you about 1.6 PPO2. You would not be at 130 feet for very long, so the exposure, while not guaranteed -- nothing is -- is not what you would expect to create a dangerous situation.

 

[halocline]

I think testing for CO would be a better investment than testing for O2 percentage. It's very unusual that an air tank will get a nitrox fill by mistake, and unless you're doing pretty deep dives, oxygen toxicity is very very unlikely. Of course, if you are diving to 120-130 feet or so and you have any reason to think you might have gotten a higher O2 tank, by all means test.

But while CO contamination is also pretty rare, it usually does mean serious illness or death, even at fairly shallow depths. And all it takes is a poorly maintained compressor or some exhaust near the compressor intake to unknowingly introduce CO into the tank. Finally, tank filling stations routinely test for O2 percentage, blend tanks, etc....so they're used to dealing with it. Very few test for CO.

Edit: wow, it look like the previous poster beat me to it!

 

[KeithG]

Q1: Are you paranoid to consider analyzing recreational air?
A1: YES!

Q2: Is this a dangerous paranoia?
A2: NO!

So have at it and enjoy your dives with a calm peace of mind.

Our modern society seems to foster all sorts of odd compulsive behaviors. Please make sure you also pressure check the tires on your car before every trip.

In the real world this should not be a concern for the average recreational diver (just like I never check my car tires since I am not driving in the Indy 500). If you limit your depth to 100 feet, who cares if you have ean32 in your tank?

I once had the situation of an operator mistakingly putting banked Nitrox into my air tank. They identified the issue as part of the final tank fill check procedure (good for them). I said my MOD for the next dive was 60 feet and that they could drain & refill or just leave the tank alone. I dove the tank without analyzing it - and survived.

My main point is that the need to analyze is situational (just like checking tire pressure). A recreational diver doing conservative dives from a shop that only does air has no need. A tek diver dragging multiple bottles of voodoo gas should analyze every one. They are very different situations. They demand different procedures.