Question on Filling Nitrox Tanks

[cummings66]

The shop I use for Nitrox fills does it while I wait, and yes they do PP blending and the mix rarely varies after a period of time, not that it can't.

So, there's not a need to wait 24 hours in my book. Here's what you do, get the fill and take the tanks home, analyze them before you dive just in case and you'll probably find that it didn't vary from what the fill was and if it did it's only a .1 or .2 from it. You do own an analyzer don't you? I consider it a must have for my own safety. Two checks are better than one IMO.

Sign the form as if it was the right mix, if he knows what he's doing it's going to be fine and if he doesn't that explains the error and why they make you wait. 24 hours is plain silly, tell them so.

 

[Jimmer]

One more vote for owning your own analyzer. Infact my shop insists on 2 independant analyzers being used on tanks they mix, not just 2 different people checking with the same analyzer, like some shops use.

 

[cummings66]

Yup, I've been in shops where they require you to look at their analyzer values and sign a log saying you got x fill. I happily do so, but then I analyze it with my own meter because it's not the dive shop employee who's risking their neck, it's me.

Piece of mind is worth the cost of ownership.

For what it's worth, if I could I'd find another shop. I'm in the same boat in that I have to travel close to 200 miles to get a Nitrox Fill, so if that shop did something stupid like this I'd go beserk... It's not like I'm coming back 24 hours later, you fill it now with Nitrox or I walk out the door without it. I'll wait a while, but I certainly will NOT come back the next day for it, I'll fill my own first.

 

[Atticus]

I asked him if I needed to get my own analyzer so that I could take them with me and test them myself and he had some other excuse...I had to sign off on the mix before leaving the shop and because of his liability he had to make sure it was the proper analysis.

Hi Denise,

For a couple of years I was the "shop monkey" doing nitrox fills. My procedure was to do the math, fill the tanks, analzye the tanks, have the customer analyze the tanks, sign the book, and off they went.

My normal turn around time when I was in the shop was 30 minutes.

My suggestion is to have a talk with the store manager.

You could explain that you live a good distance away, that you would like to purchase an analyzer from him, that you will analyze the tanks in their store, fill out the log book, etc, and that you will analyze the tanks again with your analyzer prior to diving them.

Since you are filling out the log book stating that you have analyzed the gas, you are taking responsibility for the accuracy of the measurement. This gets them off the hook if your families attorney (after an accident) claims that they represented that the tanks contained gas xyz which differs from the actual contents. In practice this type of claim holds little merit since every nitrox training organization teaches you to analyzer your own tanks.

The typical dive shop in Monterey, CA has you analyze the tanks as soon as the fill is complete, sign their book, and off you go. We do the same thing at two of the three shops here in Reno.

Best of luck and let us know how it goes.

 

[plot]

Well, I was gonna recommend getting your own analyzer and checking it yourself the next day too, but I see that's already been covered.

Worse case scenerio, you get home, the next day the % is horribly off (very unlikely) and you dump the tanks and try again next time. You'll be saving yourself a trip 99% of the time.

Should check it before you dive it too, that way if something is screwy (even if it's your analyzer), you can dump it and use normal air if need be.

 

[denisegg]

How much does an analyzer cost?

 

[fire_diver]

I too am in the 100+ miles to get nitrox fills. Even though my shop will do it while I wait, I don't have any time to wait. It's another 4 hours to the dive site. I usually have barely enough time in a day to drive to the site, do 2 dives and drive home.

That's why I am working on doing my own PP blends. I already have access to the compressor (and I maintain it) so I just need the whip and bottles. But I have other costs right now, so maybe in another month or two at most. Oxyhacker rocks!

Comrade Stroke

 

[Meng_Tze]

How much does an analyzer cost?

I would guess between $100 and $300.

Just look at scuba store websites and /or search.

 

[JEScholz]

How much does an analyzer cost?

With a soldering iron and a volt / ohm meter, you can build one! Check out Vance Harlow's Oxy Hacker's Companion http://www.airspeedpress.com/newoxyhacker.html

 

[Jimmer]

wow, you guys are really making me appreciate how close my dive shop is!! My instructor lives across town here, I'm working on my DM with him, and I've had him open the store at ungodly hours to mix my doubles for me, I've had him toss the keys to me for air fills. Plus I'm got one shop within a 30 minute drive that does Nitrox, and 2 more within an hour drive. I'll definetly stop taking that for granted!!