Nitrox scenario question

[Barracuda2]

You're on a live a board diving 4-5 dives a day using 36% nitrox during the week. On one of those days, a morning dive is planned to 140' and everybody is going to use 21% or just "air". You are obviously not filling your own tanks or switching them out between dives. Here is the question: Do you still analyze your cylinder before doing that dive? or do you just trust that the crew gave you a cylinder with air?

I've been on trips where most guests just trust the crew since nitrox is not going to be used on that dive. When we dive air on a 1-2 tank day trip, we don't analyze, and I think some divers carry this idea over to multiple days of multiple diving---no nitrox,no analyzing. What do you think?

 

[redacted]

If they are pumping nitrox on the boat, I analyze every tank before I use it.

 

[Zoomer]

By habit I always check my cylinder for pressure and contents both at the shop where I pick them up and on the boat before the dive.... but I have my own O2 analyzer.

 

[Randy43068]

You're on a live a board diving 4-5 dives a day using 36% nitrox during the week. On one of those days, a morning dive is planned to 140' and everybody is going to use 21% or just "air". You are obviously not filling your own tanks or switching them out between dives. Here is the question: Do you still analyze your cylinder before doing that dive? or do you just trust that the crew gave you a cylinder with air?

I've been on trips where most guests just trust the crew since nitrox is not going to be used on that dive. When we dive air on a 1-2 tank day trip, we don't analyze, and I think some divers carry this idea over to multiple days of multiple diving---no nitrox,no analyzing. What do you think?

First of all, doing a 140 footer on a single 80 is nuts, if that's the plan.

Second, I'd damn sure be analyzing the gas if you're using it all week long.

And....... fer sure I'd want to KNOW what was in the bottle(s) for a hundred forty footer.

 

[Barracuda2]

First of all, doing a 140 footer on a single 80 is nuts, if that's the plan.

To be specific, I am referring to the Belize Blue Hole; it's dove routinely on a single 80.

 

[Randy43068]

To be specific, I am referring to the Belize Blue Hole; it's dove routinely on a single 80.

I know it's done Denny, but it's still nuts and irresponsible IMO. There is no room for any error. If you lose gas most likely no one will have enough to get both you and your buddy back to the top.

As far as analysing, I'd to it no matter.

 

[h2odragon1]

Always analyze!!
If you are diving a 36% profile, how much trouble can you get into if it's actually 38% or 34%??
If you are making multiple dives, you can exceed your maximum exposure time.
Ultimately, it's your life/health.

 

[DandyDon]

Always analyze!!
If you are diving a 36% profile, how much trouble can you get into if it's actually 38% or 34%??
If you are making multiple dives, you can exceed your maximum exposure time.
Ultimately, it's your life/health.

He was asking about the Air tank.

Yeah, I'd analyze the air tank too, especially in Belize - but then I had a lousy Op when I was there.

 

[pir8]

Yes you are responsible to analyze your tank.

 

[AzAtty]

If they're using both 36% and air over different days, I'd be analyzing every cylinder I dive. One can't be certain that an over-tired crew member servicing several dozen cylinders did not fill an "air" cylinder with something other than air.