O2 Analyzer

Any recommendations, warnings, issues, concerns with O2 analyzers? I've been
Nitrox certified and looking to acquire my own for all the obvious reasons.
Just curious to know and learn from others who have been in a similar
situation.

Thanx In Advance...

> Any recommendations, warnings, issues, concerns with O2 analyzers? I've
been
> Nitrox certified and looking to acquire my own for all the obvious
reasons.
> Just curious to know and learn from others who have been in a similar
> situation.

I had one but decided not to keep it because the cartridge needs to be
replaced regularly and it's expensive. Everywhere I dive nitrox has an
analyzer. It was perhaps more convenient and safer to have my own, but not
cost-effective. A note on convenience: I had to find an air tank to use
for calibration and that was sometimes difficult to do when almost everyone
uses nitrox and the divers on air might be reluctant to have you "tampering"
with their tank.

Jeanne

>I had one but decided not to keep it because the cartridge needs to be
>replaced regularly and it's expensive. Everywhere I dive nitrox has an
>analyzer. It was perhaps more convenient and safer to have my own, but not
>cost-effective. A note on convenience: I had to find an air tank to use
>for calibration and that was sometimes difficult to do when almost everyone
>uses nitrox and the divers on air might be reluctant to have you "tampering"
>with their tank.
>
>Jeanne
>
>

You might be safer setting up a "calibration tank" using 40 percent
02...because generally speaking its the O2 possibly being higher than you think
it is that is a danger in diving...

You want to make sure any O2 meter you use will ACTUALLY show a high O2 level
if thats what it is exposed to...that fact it shows 21 percent when exposed to
21 percent isnt nearly as an effective test....

And Ive been under the impression that when O2 meters crap out, they tend to
fail first by not showing high o2 levels when in fact they exist....

Just my opinion

take care

Blll

Any of the O2 analyzers out there will work. Some are a bit easier to use
than others. For an inexpensive one try Oxycheq's "El Cheapo". You can
also build your own. The analyzer is really nothing more than a voltmeter.
Plans are available from "The Oxygen Hacker".

Most people calibrate with atmospheric air - usually close enough. Think
about how accurate you need to be. How much will an error of .5% affect
your dive plan? How about 1% ? What about a 2% error? If you want to
calibrate to compressed air it will be more accurate because most of the
water is eliminated. You can also measure the amount of water in the air
(humidity) and apply a correction to the reading.

Using a "calibration tank" of EAN40 would only increase your accuracy if you
could analyze the "calibration tank" at a significantly higher level of
accuracy. The errors would be additive. Checking your sensor on pure O2
(or high oxygen EAN) will let you know if your sensor is failing, because
they fail at the high end first. Calibration of O2 analyzers to pure
oxygen is sometimes recommended, but raises a problem. Since most analyzers
have only single point calibration capability, it is better to calibrate
them at a point close to the where you will be actually be taking readings.


--


Safe diving,

Dale Bennett
Captain Dale's, Inc.
Enterprise Marine, Inc., Dive Charters


"BllFs6" <bllfs6@aol.com> wrote in message
news:20040908102538.07554.00000368@mb-m18.aol.com...
> >I had one but decided not to keep it because the cartridge needs to be
> >replaced regularly and it's expensive. Everywhere I dive nitrox has an
> >analyzer. It was perhaps more convenient and safer to have my own, but
not
> >cost-effective. A note on convenience: I had to find an air tank to use
> >for calibration and that was sometimes difficult to do when almost
everyone
> >uses nitrox and the divers on air might be reluctant to have you
"tampering"
> >with their tank.
> >
> >Jeanne
> >
> >
>
> You might be safer setting up a "calibration tank" using 40 percent
> 02...because generally speaking its the O2 possibly being higher than you
think
> it is that is a danger in diving...
>
> You want to make sure any O2 meter you use will ACTUALLY show a high O2
level
> if thats what it is exposed to...that fact it shows 21 percent when
exposed to
> 21 percent isnt nearly as an effective test....
>
> And Ive been under the impression that when O2 meters crap out, they tend
to
> fail first by not showing high o2 levels when in fact they exist....
>
> Just my opinion
>
> take care
>
> Blll

>Using a "calibration tank" of EAN40 would only increase your accuracy if you
>could analyze the "calibration tank" at a significantly higher level of
>accuracy. The errors would be additive. Checking your sensor on pure O2
>(or high oxygen EAN) wi

Yeah...your right that pure 02 "might" be a better calibration tank than 40
percent 02....and yes your calibration is harder (at least in theory) for using
40 percent because its hard to get "exactly" 40 percent.....

But the whole point isnt to get an exact calibration...its to make sure that
the oxygen sensor hasnt gone tits up and isnt giving WAY wrong
readings....particularly at 02 levels that are likely to be in the range of the
mix you plan to use...

which reminds me of these fools who think you can calculate deco to a precision
of few percent and think it really means anything.....

So, it really comes down to whether you want to fool with getting pure 02, or
just get a 40 percent nitrox tank measured with a couple different sensors at
the time of the fill....or just mixed carefully by the partial pressure
method...


Reminds me of something someone posted here a few years ago....they were on a
commercial dive boat....someone grabbed a tank and did a deep dive only to find
out that it was 40 percent!

Well, the story ended up with the dive operator screaming about having nitrox
in "air" tanks, yet the dive operator ended up having air in the boats "nitrox"
tanks on the boat as well...or maybe the "air" tank filled with nitrox was one
the diver brought but someone else grabbed.....

Whose the fool(s) here? :)

trust but verify :)

take care

Blll

>Any recommendations, warnings, issues, concerns with O2 analyzers? I've been
>Nitrox certified and looking to acquire my own for all the obvious reasons.
>Just curious to know and learn from others who have been in a similar
>situation.

Take a look at the Analox O2EII. It's a lot tougher than most. Easy to use.
They were bouncing one off the floor at DEMA. About $280. Sensor life +/- 4
years. Sensor warranty 3 years. I bought one, we use one at the shop and we
sell every one we get in stock. Something must be good about it :) Look at
your local dive shop.


Later-

bj
Chicago

In article <20040908131524.05051.00003592@mb-m24.aol.com>,
bllfs6@aol.com (BllFs6) writes:

>But the whole point isnt to get an exact calibration...its to make sure that
>the oxygen sensor hasnt gone tits up and isnt giving WAY wrong
>readings....particularly at 02 levels that are likely to be in the range of the
>mix you plan to use...
...

This bothers me. I would think that any sane diver would start with a tank
that contains a KNOWN O2 level. Checking it again with another sensor is
a double check. If it doesn't match closely the correct resonce is to not
dive with that tank untill you know what went wrong and why.

In other words, if the sensor has gone "tits up" (what a term!) and gives a
way wrong readign -- well the dive should know something is wrong because
the tank does NOT show the O2 level it is supposed to have.

--
Charlie Hammond -- Hewlett-Packard Company -- Ft Lauderdale FL USA
(hammond@not@peek.ssr.hp.com -- remove "@not" when replying)
All opinions expressed are my own and not necessarily my employer's.

"Charlie Hammond" <hammond@not@peek.ssr.hp.com> wrote in message
newsnI%c.10034$ie4.8076@news.cpqcorp.net...
> This bothers me. I would think that any sane diver would start with a
tank
> that contains a KNOWN O2 level. Checking it again with another sensor is
> a double check. If it doesn't match closely the correct resonce is to not
> dive with that tank untill you know what went wrong and why.
>
> In other words, if the sensor has gone "tits up" (what a term!) and gives
a
> way wrong readign -- well the dive should know something is wrong because
> the tank does NOT show the O2 level it is supposed to have.
>

Absolutely! I have nine sets of doubles and I don't know how many singles.
I don't even dive air until I have analyzed it before the dive. I once lent
another diver a 40 CF stage with EAN50 (70 FT) and when I got it back it had
100% O2 in it with no change in markings. I analyzed it before using it and
was quite surprised as the reading kept climbing. I checked it again with a
second meter just to make sure. Needless to say, I was none too happy.

--
Safe diving,

Dale Bennett
Captain Dale's, Inc.
Enterprise Marine, Inc., Dive Charters

In article <0eM%c.149548$Fg5.89928@attbi_s53>, Cpt. Dale Bennett
<captndale@comcast.net> wrote:

€ I once lent another diver a 40 CF stage with EAN50 (70 FT)

Awful lot of liability there, "captain".

--
"We're going to rush the hijackers."
-Jeremy Glick, aboard United Airlines flight 93, September 11, 2001

The one I hate is the O2 Stick. I've never been able to get consistent
readings off the same tank, minute to minute, with one. They prompted
me to get my own to take on dive boats.

--
Chuck Tribolet
triblet@garlic.com
http://www.almaden.ibm.com/cs/people/triblet

Silicon Valley: STILL the best day job in the world.


"DownTime" <DownTime@nospamforme.com> wrote in message news:MfD%c.34199$w_4.4490743@twister.tampabay.rr.c om...
> Any recommendations, warnings, issues, concerns with O2 analyzers? I've been
> Nitrox certified and looking to acquire my own for all the obvious reasons.
> Just curious to know and learn from others who have been in a similar
> situation.
>
> Thanx In Advance...
>
>