Nitrox

[HammerNoMore]

I want to respond to questions from several of you. How do I reply to multiple posts with the text from the poster like you did in this post?

Looks like your question has been answered Christi. Another hint I would add is to use the "Preview Post" until you get comfortable with it.

James

 

[Scuba_Steve]

This one James......

Blue Angel let me get 32 for dive one, but we had a bunch of people who got along real well on the boat and we decided the day before where we were going to do dive one. With a MOD of 130' you can do most first dives in Coz on EAN32, even the Throat if you are real carefull to exit at the top. (I certainly wouldn't, but you'd be legal.)

James

Which is the same one that Christi used, and understood the same thing that I did of that statement.

And "No" you wouldn't be "legal" either, on that dive with that mix......

That's NOT a "legal" limit using backgas/bottom mix calc's by any agency's yard-stick.

It EXACTLY why Christi wouldn't let folks use 32Mix on the Throat as she stated as well.

It should be obvious as to why, but evidently it's not.

Of the few times that I have done that dive, I would have ALWAYS been over the yard-stick rule. The mere statement that you "could" do the throat "legally" on EAN32 is just not correct.

Regards

Steve

 

[HammerNoMore]

Which is the same one that Christi used, and understood the same thing that I did of that statement.

Except the first time you a) left out the bold if that went along with the statement b) left out the following statement where I said I would not do it and c) left out the statement then as well as now where I said I wouldn't allow it as a dive op. Therefore totally twisting my words.

And "No" you wouldn't be "legal" either, on that dive with that mix......
That's NOT a "legal" limit using backgas/bottom mix calc's by any agency's yard-stick.[
It EXACTLY why Christi wouldn't let folks use 32Mix on the Throat as she stated as well.
It should be obvious as to why, but evidently it's not.
Of the few times that I have done that dive, I would have ALWAYS been over the yard-stick rule. The mere statement that you "could" do the throat "legally" on EAN32 is just not correct.

Well, I've never exceeded 130 ft on Devils Throat. But like I said, and you chose to ignore, I exit at the top to be conservative. Just because you exit deeper than that doesn't mean it can't be done.

James

 

[AggieDiver03]

Not to hijack the thread, but what does your instructor friend consider a "cheap" analyzer? I was talked into an OMS OX-ANII analyzer by my LDS ("Here's your analyzer... that'll be $275.00...).

I haven't done too much research on them either, but primarily he advised against purchasing the least expensive one because you though not always true, quality often costs a little more. And no i wouldn't consider $275 cheap.

If i recall correctly the "El-cheapo" is one of the build your own kits that you can purchase?? My nitrox instructor uses one that he built himself and he's happy with it.

I shouldn't have used the word "cheap". One reason to purchase your own analyzer is that you want to get an accurate reading of your gas mixture so that you can dive safely. Therefore, it doesn't make a whole lot of sense to get something that will just give you a ballpark reading, since that's not accomplishing anything more really that blender. So if you're purchasing one for safety and reliability, then it may cost a little more.

Basically, research analyzers and purchase one that meets your needs...if it's a less expensive analyzer then go for it. In my opinion, if i'm going to buy one, i'm going to make sure it's a good one that will actually serve a purpose. While i don't want to break the bank with a $1000 analyzer, i will probably spring for one that is not at the bottom of the line either.

 

[Scuba_Steve]

Uhg a Moderator with 1500 posts.......yup never wrong, and uhmmmm you can't twist word with a copy and paste pal.....

Did I leave out the last couple words?? Yup, so what, I'd hope you would never use EAN32 to 130 either..THAT'S NOT MY POINT.......READ AGAIN.

My SOLE point was, YOU saying that it's LEGAL (I know what you mean by that, so that's a good enough term for me, I don't mix words as you'll soon see) is INCORRECT.

Unless you think you're decompressing at 130 with your backgas ????? Nottt.

You don't have to exceed 130 to exceed your max PO2 for EAN32 as a backgas.

Maybe we should re-educate some safety into people if we have to continue to tell them the same things over and over. I personally don't run loosey-goosey with the PO2 "thing".

Christi and I got the same thing from your statement, which means something probably....hmmmmmm.

I'm not sure what angle you're looking at it from, but as for Christi (sorry if I'm speaking for you Christi, but I know you'll agree) and myself, if we're escorting a diver which may or may not be a paying client (for her), there's no way in hell (And I will reiterate one more time) that we would we would even consider using EAN32 on the Throat.

Wether I'm doing a Rec dive or a Tec dive, my personal P02 limit does not exceed 1.35 for backgas, but the yardstick which we all can agree on is 1.4, which will ALWAYS be exceeded on the Throat. It's a non-starter. The risk outweighs the reward.

It's simple man, get over it. 130ft, the depth YOU stated, is out to lunch for that mix.

 

[Christi]

Calm down. However, Steve is correct. I would never consider allowing a diver to dive the throat or dive to 130 with a 32% mix as stated before.

According to the PADI EAN 32% table:
100 ft = O2 p.p of 1.29
110 ft = O2 p.p of 1.39 (pushing the limit right here)
120 ft = O2 p.p of 1.48 (headed towards contingency limits)
130 ft = O2 p.p of 1.58 (pushing the contingency limit)

Using the MOD formula (imperial version): 46.2/O2% - 33, we get a maximum depth for 32% of 111ft

46.2/.32 -33 = 111.37

Maximum contingency depth formula (imperial version) 52.8/O2% - 33 we get:

52.8/.32 - 33 = 132

Like I said, I do not allow nitrox dives to be planned beyond 100 ft with my operation. The risk is not worth the reward. If someone doesn't llike my policy and wants to put themselves in an unreasonable risk situation, they can do it with another operator.

 

[ggunn]

Calm down...

For a minute there I was beginning to think I had somehow been sent back to rec.scuba... ;^)

 

[Scuba_Steve]

She loves me..........

OK, good post, and like I said, I have a healthy respect for Oxygen at depth, and simply wouldn't tolerate anyone I'm with, screwing around with the depths, much less let a paying client ruin my reputation.

Fortunately I've never had to take care of, never mind witness an Oxtox situation, BUT, I have had to train for them. We were even evaluated on video being the resuer and the rescuee so we would get a feeling for what it would take to properly rescue a toxing diver.

With any luck at all, I'll never have to see how I'd fare in a real-life situation.

Rec.scuba.........I've heard about it

Regards folks

Steve

 

[5615mike]

Just wondering about diving Nitrox in Coz. A couple of questions:

1) do I need to bring my own analyser or are they on the boat? I assume that since the op will pick up from the jetty that you don't have to make your way to the shop to do this.
2) do they dive standard mixes or do you need to request a mix (you'd need to know the diving schedule for the day)
3) is there somewhere (or someone) who can give me some depths for the likely dive sites?

Don't ever dive EANx without testing with your own rig IMO. You don't know how or when the last one was calibrated or if it even works properly

My last trip to Coz in May I did 12 dives on EANx and 4 on air. Of those 12 tanks, only one tank was w/in 3 points of labeled mix. When your approaching MOD that gets dicey. Had to dive air at Punta Sur b/c the tank they had for me marked 32 was 36 and the 36 for second dive was 38.

 

[HammerNoMore]

Uhg a Moderator with 1500 posts.......yup never wrong, and uhmmmm you can't twist word with a copy and paste pal.....

Fine, whatever you say. You think that quoting half a statement to make it look like I was endorsing something I clearly wasn't is not twisting my words? I'm not going to get into a pissing contest with you with that kind of logic. I'll just make judicious use of ignore.

My SOLE point was, YOU saying that it's LEGAL (I know what you mean by that, so that's a good enough term for me, I don't mix words as you'll soon see) is INCORRECT.

Hey, you want to derail a thread with your own personal opinion of what MAX PPO2 is be my guest. I've discussed it before and I'm not going to get into it with you.

*PLONK*