Nitrox: Should I be worried?

[Diver0001]

I recently did the course work and became Nitrox "Certified", but haven't yet used a tank. Now I'm in Cozumel, doing a week's worth of diving and the outfit I'm with said they have nitrox available, if I want it for $10 more. I'm interested in trying it, but I don't think that I will be able to analyze the air in the tank. I just arrive at the marina, jump on the boat, and they setup my gear, attach the tanks, etc.

My PADI Nitrox course made me scared enough about using enriched air if I cannot check the gas myself, and a buddy back home tells me the guy who runs one of the LDS' had his brother die from bad air in Mexico...

am I being unreasonably paranoid?

Always ... ALWAYS ... check your own gas. period. If you can't do this then don't dive Nitrox. It's that simple.

You don't necessarily need to *own* your own analyzer but you at least need access to one that you trust is calibrated correctly.

R..

 

[KentB]

I have my own fill station and always analyze.
If I’m away from home on a trip even if I get air or top up with air I always analyze, it takes 30 seconds so I don’t see why people don’t.

I also don’t get why people don’t analyze tanks they get with just air.
I didn’t either when I started diving but as I gained experience and set up my own fill station I realized how naive that is.
I bought a compressor around dive 30 or so and starting mixing nitrox around 80 so for that time span in between I didn’t because I wasn’t capable of different mixes but as soon as an O2 bottle came around now every tank gets checked.

 

[abnfrog]

their is a famous post on here about a guy to arrogant to analyze he died ......enough said

 

[Caveeagle]

That’s an interesting thought. I could see at shops that fill both air and Nitrox someone messing up.

Don’t forget about the possibility of someone filling a rental tank offsite, or using a tranfill whip to boost up the o2 levels. A shop would probably just top off an “air” tank with air, and never even check it’s contents.

Now If you are diving 2-3ATM , for one or two dives, and accidentally get EAN32, it probably not going to cause any issues. But if you are diving deep and/or doing a lot of repetitive dives where your 02 CNS clock is a consideraton... you could run into trouble.

...why risk it.

 

[ScubaMarc]

I have no doubt that some operators get in the habit of assuming their divers are okay with assuming the mix is correct.
I also think you are totally correct and justified in not following that plan. Ask them where the analyzer for diver use is, and where in the process you can utilize it.
You may get some resistance, but probably not outright denial.

I was very surprised a few years ago when Captain Don's in Bonaire expected me to take their word for it on the mix. They looked at me like I had two heads when I stepped up to test my cylinders, but did not refuse to allow it. And, the mixes were NOT as labelled. Not wildly off, but enough to set a different mix on my dive computer.

One year in Curacao, I ask for 32%, they did care if I checked or not, but I did, it was 40%. I gave it back and used air.

 

[Manatee Diver]

One year in Curacao, I ask for 32%, they did care if I checked or not, but I did, it was 40%. I gave it back and used air.

Of course they don't care, they aren't the one that would die if you end up with the wrong mix.

 

[AdivingBel]

One year in Curacao, I ask for 32%, they did care if I checked or not, but I did, it was 40%. I gave it back and used air.

Of course they don't care, they aren't the one that would die if you end up with the wrong mix.

For me, this thread has run its course. It's smart to analyze your tank if you're diving nitrox. Variances occur. As far as the blanket "they don't care"...that's BS. If you truly believe that then find a different hobby and quit scaring the new divers. Jeez

 

[yle]

I recently did the course work and became Nitrox "Certified", but haven't yet used a tank. Now I'm in Cozumel, doing a week's worth of diving and the outfit I'm with said they have nitrox available, if I want it for $10 more. I'm interested in trying it, but I don't think that I will be able to analyze the air in the tank. I just arrive at the marina, jump on the boat, and they setup my gear, attach the tanks, etc.

The boat probably has an analyzer you can use, just ask them. I was in Coz last month, shop I dove with kept an analyzer on their boat. A shop I dove with a few years ago in Coz wanted to do all the analyzing for their guests... but any reasonable shop should accommodate your request to analyze your own tanks.

Using nitrox occasionally is a good habit to get into, since it's available most places you will dive and should be a consideration for your dive planning.

The boat should absolutely have a testing tool for you to use - 32 and 36 are common there but 36 can get mislabeled 32 - I've never seen it but it's possible..

I've seen it, last month in Coz. We asked for 32, I had my analyzer... three of our tanks were 32, one was 36. They weren't labeled anything. DM shrugged, switched the tank for another that he guessed was 32 (and he guessed right.) In the past I've also been given a "nitrox" tank that was filled with air, found out only by analyzing myself.

 

[Manatee Diver]

For me, this thread has run its course. It's smart to analyze your tank if you're diving nitrox. Variances occur. As far as the blanket "they don't care"...that's BS. If you truly believe that then find a different hobby and quit scaring the new divers. Jeez

I suppose I should expand on my post, I'm not implying that the fillers have malice or aren't taking due care to ensure that your tanks are properly filled, simply that it is no skin off their back if you aren't willing to take the 30 seconds to test the tank. They did their best, if you aren't willing to follow accepted safety practices to double check the mix that is on you.

Personally I feel that it is worth the time, even if the last 9 tanks read 36% on the nose, I am still going to check the 10th tank.

 

[Storker]

I would not dive a tank filled with partial pressure that I did not analyze.

I agree.