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cshel
10-12-2007, 18:48
How many of you have your own analyzers?

Boris and I are taking our Nitrox class next week because we are going wreck diving on Oct 27th and 28th off the coast of NC! We have been studying our book and we know that we will ALWAYS check our own tanks to verify the mix. We we just wondering how many other divers have their own gauge or if you use the dive shops gauge?

in_cavediver
10-12-2007, 18:55
I bought/made my analyzer after I realized i was getting complacent with premix nitrox. Now, I have ZERO excuses for not always knowing my mix. (well, if I care. 20ft max dives could be on anything 21%-40% without really caring about the mix. You're so far from any limit it doesn't really matter)

Charles R
10-12-2007, 19:00
I have this one its simple and easy to use http://www.scubatoys.com/store/detail.asp?PRODUCT_ID=AmoxtecO2EII

subsur
10-12-2007, 19:18
i don't own one (i don't dive Nitrox although i got certified) but if you are planning to dive Nitrox then you should get it, especially if you are travelling somewhere. it gives you a piece of mind. O2 (oxygen) analyzers are expensive but they are worth it. you can chose from many different brands. ST sell some of them as well.

dludwig
10-12-2007, 19:31
so far I have to trust the analyzer of my NITROX "supplier" but eventually plan to have my own

Damselfish
10-12-2007, 22:10
Rarely do I see a problem using a shops analyzer. The 2 occasions I wished iI had my own were in fairly remote places. If you travel a lot and dive Nitrox alot, it might be worth it depending where you go. If you don't dive a lot and go to pretty mainstream places it might not be worth it. Keep in mind the sensor is a consumable item that ages, so if you don't use it much that could be a pretty high cost per tank to analyze.

RoadRacer1978
10-12-2007, 22:20
Not nitrox certified yet, but will be on the wishlist after I get the certification.

Scubastud16
10-13-2007, 01:37
I just use the gauge at the shop. Make sure it's calibrated to air (20.9 percent), then check the tank (or watch the employee do it till I'm satisfied).

scubamarc
10-13-2007, 08:18
In Curacao, ocean divers, I asked for 32 mix and luckily i had my own analyzer. They gave me 24 mix. I would have been hurting from this mistake.

cshel
10-13-2007, 11:06
In Curacao, ocean divers, I asked for 32 mix and luckily i had my own analyzer. They gave me 24 mix. I would have been hurting from this mistake.

I've heard lots of stories like that.

I'm going to hold off on buying one right now. We take the class Monday and dive on 10/27 (two wrecks) and 10/28 (two more wrecks) with our teacher and others from the local dive shop. I'm not sure how much Nitrox diving we will do in the future.

Aussie
10-13-2007, 11:25
I share the O2 Analyzer with my buddy. Saves the cost so we can spend on other things like diving trips.

Aussie

CompuDude
10-13-2007, 14:21
I have my own, but I was never uncomfortable using the shops' (or boat's) analyzers. May be a reflection on our local boats and shops, however.

I have my own now, however, and I always bring it on boats so I don't have to wait my turn to borrow one, and as a general backup should something happen to theirs (happened once... no more Nitrox that day!) and anytime I travel to someplace I may be using Nitrox.

So I voted Yes... but I DO still trust others' analyzers... in the right situation.

Dive-aholic
10-13-2007, 15:26
I have my own analyzer. I analyze all gas I get from shops that can provide nitrox fills. Just because you're getting air from the shop doesn't mean then didn't get it from the right set of banks. Also, I always analyze right before a dive. It's part of my routine. I'm not going to trust my memory or a piece of tape on the tank. I've also had the experience of not having a working analyzer available....other than my own.

ScubaBoy
10-14-2007, 18:01
What with an analyzer being so critical, how does one analyze your analyzer? Also, how often does the sensor have to be replaced? Is it after so many uses, or so much time?

js1scuba
10-14-2007, 18:54
I got certified for using nitrox in 1989. I bought my first analyzer then and have bought many more over the years. Today my company manufactures analyzers and we are the US distributor for the OxySPY used by all the major liveaboards and by close to 10,000 divers.

If you have already invested in all of your dive equipment and a nitrox dive computer, a quality oxygen analyzer is the appropriate tool to go with it.

With your own unit you are always guaranteed that YOU can check your cylinders when you want to and in the manner with which you become most comfortable. The minor investment of $200-300 for a tool that will be with you for years and is critical to your nitrox diving is warranted. Expect you will replace the oxygen sensor in your unit every 12-24 months depending upon the use you give it. Replacement sensors run about $65-85 depending on the brand.

You will hear the argument that the "shop" is to provide one, or the "resort" will have one. I cant tell you how many resorts I go to where the unit I bring becomes the unit to use cause thier sensors are crapped out. Or a dive center who has a tank monkey who does not know how to calibrate the unit they have.

Make the investment you will be happy you did.

Cheers

in_cavediver
10-14-2007, 20:50
What with an analyzer being so critical, how does one analyze your analyzer? Also, how often does the sensor have to be replaced? Is it after so many uses, or so much time?

I have two simple mediums to validate my analyzer. The first is simple ambient air. Should be 20.8. The next is my O2, either med bottle of deco bottle. They ONLY get hooked to O2 tanks so no chance of air fill. It should be 99.9 or 100. Provided both are good (within a percent or two at the 100), the sensor is good.

I just replaced mine because it refused to calibrate to 20.8. New sensor - no problems.

JugglingMonkeys
10-14-2007, 23:12
Oh no! Another expensive thing to buy!
:smiley5:

So, which is the best one?

charlesml3
10-15-2007, 09:49
Why buy one at all if you can use the shop's analyzer? I always email the dive op before we head down and make sure they have an analyzer I can use there. I calibrate it to a tank with air and then analyze my own tanks. As long as they have one that you can use, I see no reason at all to go out and buy one.

-Charles

CompuDude
10-15-2007, 12:27
Why buy one at all if you can use the shop's analyzer? I always email the dive op before we head down and make sure they have an analyzer I can use there. I calibrate it to a tank with air and then analyze my own tanks. As long as they have one that you can use, I see no reason at all to go out and buy one.

-Charles

Because sometimes a shop analyzer can break, be wrong, or be poorly maintained. And even if that's not the case... sometimes, people dive places other than a dive shop. ;-)

No Misses
10-15-2007, 12:57
I use the shops analyzer. They have 3 units available so waiting is a non issue. The only other place that I get fills is on the MV Playmate (livaboard) and they have at least 2 analyzers on board for every trip.

ScaredSilly
10-15-2007, 13:11
Not that I do not trust the shops (if I did not why would I have them supplying me with gas) I have one for the conviencence. Sometimes there is a line to use the shops so having my own is great. Especially when they say stop by at 9pm to verify - I just no thanks just have them at the boat at 9am and will do it myself with mine. Then I do not have to worry about any mucking about til I dive.

Dive-aholic
10-15-2007, 19:26
Why buy one at all if you can use the shop's analyzer? I always email the dive op before we head down and make sure they have an analyzer I can use there. I calibrate it to a tank with air and then analyze my own tanks. As long as they have one that you can use, I see no reason at all to go out and buy one.

-Charles

How do you know you're calibrating it to air? Maybe the shop screwed up and filled that tank with nitrox...

Also, how old is the sensor? How well maintained is the analyzer? Sorry, but that's my life. In fact, I own an oxygen/helium analyzer.

js1scuba
10-15-2007, 20:24
Why buy one at all if you can use the shop's analyzer? I always email the dive op before we head down and make sure they have an analyzer I can use there. I calibrate it to a tank with air and then analyze my own tanks. As long as they have one that you can use, I see no reason at all to go out and buy one.

-Charles

How do you know you're calibrating it to air? Maybe the shop screwed up and filled that tank with nitrox...

Also, how old is the sensor? How well maintained is the analyzer? Sorry, but that's my life. In fact, I own an oxygen/helium analyzer.


Hi Rob,

A proper dive center segregates its cylinders. You have been to my shop so you saw how we keep it all seperate. Air tanks in one place, nitrox in another. However most analyzers when turned on will read in the low oxygen range 20.0-22.0 oxygen. The variance will be with altitude, humidity, sensor life etc. If one puts it on a flow meter and attaches that to a cylinder it's pretty easy to see if whats coming out is higher or lower than the base setting. If it is then you just get another verifiable cylinder to calibrate on. It is this one reason why the Oxyspy unit with it's autocalibration system that uses ambient air to calibrate works so well. You dont need a flow meter or a calibration gas cylinder thereby eliminating that one step. It works great on boats where all are diving nitrox and you dont have an air cylinder for calibration. Just push the button and go.

....
That said calibration is a critical step in nitrox (gas diving). Better to analyze twice to get it right than to make the mistake of using the wrong mix.

Cheers

kobalap
10-15-2007, 20:44
I own my own. I analyze the day of the dive at the dive site.

JugglingMonkeys
10-15-2007, 20:53
Where do you get an Oxyspy from? I notice that ST no longer carry them.

CompuDude
10-16-2007, 00:27
Where do you get an Oxyspy from? I notice that ST no longer carry them.

He carries them. He's the competition. :D

OxySpy (http://tdl.divebiz.net/index.php?main_page=product_info&cPath=10&products_id=224&zenid=e194a1253e01b87cc9afb6d64fc37651)

cummings66
10-16-2007, 09:19
That looks like a nice meter and combines a few software features to tell you things like your chosen mod based on ppo2. Pretty slick.

I think any diver using Nitrox should analyze it because shops make mistakes. So, I have my own and have from the beginning.

charlesml3
10-16-2007, 10:40
How do you know you're calibrating it to air? Maybe the shop screwed up and filled that tank with nitrox...


Because if I was on a tank of Nitrox and thought it was air and calibrated 21% there, it would not change, or change very little when I put it on a tank of real Nitrox. The % of O2 on the display should change quite a bit from 21% to 32% or 36%. The tester is only as good as the training of the operator. Besides, what does that have to do with using your tester or theirs?

Most of the testers I see in the Carribbean dive resorts calibrate to ambient air anyway. You still have to be diligent and contact the dive op ahead of time. Know before you go.


Because sometimes a shop analyzer can break, be wrong, or be poorly maintained.

Well yours "could break" too. I don't see how that's a valid argument here. I think the idea of getting Nitrox from a dive op who you suspect has poorly maintained equipment speaks for itself...

-Charles

js1scuba
10-16-2007, 20:15
Where do you get an Oxyspy from? I notice that ST no longer carry them.

Larry is always welcome to stock Oxyspy he just needs to order them.

Cheers

Dive-aholic
10-18-2007, 22:13
How do you know you're calibrating it to air? Maybe the shop screwed up and filled that tank with nitrox...

Also, how old is the sensor? How well maintained is the analyzer? Sorry, but that's my life. In fact, I own an oxygen/helium analyzer.


Hi Rob,

A proper dive center segregates its cylinders. You have been to my shop so you saw how we keep it all seperate. Air tanks in one place, nitrox in another. However most analyzers when turned on will read in the low oxygen range 20.0-22.0 oxygen. The variance will be with altitude, humidity, sensor life etc. If one puts it on a flow meter and attaches that to a cylinder it's pretty easy to see if whats coming out is higher or lower than the base setting. If it is then you just get another verifiable cylinder to calibrate on. It is this one reason why the Oxyspy unit with it's autocalibration system that uses ambient air to calibrate works so well. You dont need a flow meter or a calibration gas cylinder thereby eliminating that one step. It works great on boats where all are diving nitrox and you dont have an air cylinder for calibration. Just push the button and go.

....
That said calibration is a critical step in nitrox (gas diving). Better to analyze twice to get it right than to make the mistake of using the wrong mix.

Cheers

Very true, Joel. But not all dive centers are the same. I'm not sure if you've been to cave country, but they all use the same whips and just open and close valves. Granted, I haven't gotten the wrong fill here, but I did experience something similar on a liveaboard. The DM forgot to switch over to the nitrox banks and filled our tanks with air. She caught it before the fill was complete, but....

As for the OxySpy, it is a great unit. It was my first analyzer...bought from you... However, the ambient air thing isn't exactly true. This is just my experience, but when going from a dry climate like Arizona to a humid climate like Florida, there will be a difference in the calibration reading. Calibrating to air with a higher moisture content causes the analyzer to read a little higher than it should. I calibrated to ambient air and was getting a nitrox reading of 34%. After I calibrated to scuba air (filled from a non-nitrox supplier), I got a reading of 32%. And now I have one of your helium analyzers anyway, so I have to calibrate to a known air source.

ScubaToys Larry
10-19-2007, 18:49
Sure... We can get them in if you want some. We ended up having more people want the amoxtec (http://www.scubatoys.com/store/detail.asp?PRODUCT_ID=AmoxtecO2EII) so we stocked those heavier... but anytime you're looking for anything - we probably still have it - and just took it off the page - or we can get it!

Just give us a shout and we can get an OxySpy in right away for you!

scubajane
11-25-2007, 18:21
once again...more good info from great scuba folks i still am just tinking about an analyzer, I don't dive nitrox much. I'll have to re study the book first.

Zenagirl
11-25-2007, 20:12
I'm really struggling with the whole idea of buying my own analyzer. We've always used Nitrox when diving off boats and they've always had analyzers right on the boat, but we're planning 2 weeks on Bonaire next summer, and I can't help but wonder how many analyzers our dive op will have, etc. I've been assured by people "in the know" that there won't be a wait and it won't be a problem, but I can't help but wonder.....

Guess the struggle will go on.

Soonerwink
11-25-2007, 21:38
No, I don't dive nitrox enough to warrant the expense.

navyhmc
11-25-2007, 22:40
I am planning to go Nitrox in the near future and will probably get one-until I do I will have to rely on the kindness of strangers.

charlesml3
11-26-2007, 08:27
I remember diving with this couple in Cozumel once who were certified and said they really wanted to dive Nitrox.

I was and they weren't so I asked. They said they didn't trust the shops analyzer and were going to buy a used one off of Craigslist. It didn't come in before they left for the trip.

So I had to ask: "So why would you trust some used analyzer off of Craigslist over one they use EVERY day here in Cozumel?" All I got was a blank stare...

-Charles