Nitrox Analyzer

[RainPilot]

Sensors are around 60-80 depending on brand etc. If you get an analyser then check if you can get the cap that seals the sensor. If you can keep it from O2 in the months you aren't using it you will extend the life dramatically.

And don't let them get wet they really don't like that.

Or feed them after midnight.

 

[stuartv]

I have an Analox and am happy with it. I kind of wish the CooTwo had been around when I bought mine. Might have gotten that instead.

If you want a $100 option, there is always the $110 DIY special:

OxyCheq - EL Cheapo II Analyzer Kit

Some people say "if you're always diving with a charter operator, just use theirs." That is how I did it... until I was in Hawaii and I met my dive op at the boat. They brought me Nitrox, but they didn't have an analyzer with them and the boat didn't have one. And the shop was too far away to go get one. I dived air that day and bought my Analox as soon as I got home.

 

[The Chairman]

That's why we have forums!

 

[packrat12]

...If you get an analyser then check if you can get the cap that seals the sensor. If you can keep it from O2 in the months you aren't using it you will extend the life dramatically...

Unfortunately the idea of keeping O2 from air out to extend the life of a sensor is incorrect. Yes it will reduce the amount of anode being consumed but the anode is not the only consideration in aging a sensor. Per Analytical Industries Inc - a major manufacturer of O2 sensors - "How long can I store an oxygen sensor in its original shipping container prior to use? < 6 months at 25° C, from factory ship date to obtain the 60 months expected life in air. Note: The storage life can exceed the 6 months and or the temperature can exceed the 25 ° C (up to 40° C), but in either case the expected life will be reduced."

Specifically note that the sensor is designed or 60 months in Air. I have never seen a recommendation to use a sensor beyond that. Also, the amount of time for O2 to be above 21% for analyzers is about none so they do not age that way either. Debris, water etc is bad. So is temperature and shock.

 

[RainPilot]

It's not time above 21% that consumes anode its time above 0%. As for the rest I wouldn't argue with the manufacturer, if they say it won't last longer than 5 years I'm happy, especially since they usually last only 2 years in the analysers I've had.

My Analox also has a cap specifically to preserve the sensor so they must think it makes a difference.

Analox - O2EII PRO - BOX OF 5 SENSOR SAVERS

 

[The Chairman]

so they must think it makes a difference.

Or they think they can make a buck!

 

[packrat12]

It's not time above 21% that consumes anode its time above 0%. As for the rest I wouldn't argue with the manufacturer, if they say it won't last longer than 5 years I'm happy, especially since they usually last only 2 years in the analysers I've had.

My Analox also has a cap specifically to preserve the sensor so they must think it makes a difference.

Analox - O2EII PRO - BOX OF 5 SENSOR SAVERS

I will always cap mine as I am keeping dirt, debris, water etc out. It is just the common misnomer that reducing O2 will extend the life of the sensor when the anode consumed is not the only factor in aging a sensor that I am addressing. If you think about our CCRs, Lets say I put 40 hrs a year at 1.3 PPO2 on my sensors. I doubt I have more than 2 hrs on my 4 year old sensor in my Analox at .36 PPO2. With the 40 hrs at 1.3 PPO2 in mind, I still am only adding about 10 additional days air exposure to my CCR sensosr then if it had not been used and stored in air (Considering a 6x increase in anode consumption @ 1.3 vs .21 when considering that the sensor output is fairly linear for the range and that the increased consumption of the anode should also be fairly linear). I also know no one that stores their CCR sensors sealed, although we replace them annually. My opinion is that the O2 consumption for a sensor within the designed lifespan window is irrelevant for air. It is only relevant for long-term high O2 exposure as seen in the medical industry.

 

[Tbar]

I have two:
1) The OxyCheq El Cheapo II, OxyCheq - EL Cheapo II Analyzer Kit I would suggest these extension options the "10 Turn Potentiometer For El-Cheapo II" OxyCheq - 10 Turn Potentiometer For El-Cheapo II and "Expedition BC Flow Restrictor with Nozzle" OxyCheq - Expedition BC Flow Restrictor with Nozzle
Note you have to build this unit. There are also plans on the internet for a similar design (its basically a volt meter with an offset), most parts are quite cheap and generic, but you still need the sensor and that is the large part of the cost.

2) Cootwo DiveNav - Products - cootwo. if you get this one make sure you go through the setting and change the 02 sensor life from 12 months to 24 months (you can still change the sensor at 12 or 18 months but wont get a 'lock-out'. When it reaches the expiry it stops. Also be aware the CO needs calibration at 12 months and when this is due, mine has also blocked calibration of 02. Without the calibration CO gas you cannot calibrate the CO yourself.

I provide Nitrox to my dive buddies and provide the two analysers. Most prefer the Oxycheq product as it has the 'traditional' knob to calibrate. I tend to use the Cootwo and if traveling take the Cootwo as it lets me check both 02 and CO.

The sensors for both cost about the same and will have the same life, given same conditions.

 

[boulderjohn]

I got my nitrox certification in 2002, and I decided not to buy my own analyzer then. For more than a dozen years I relied on the whoever was supplying the nitrox to have an analyzer for me to use. Check my profile--I dived nitrox in just about every place I have visited. After that time I developed a need for a trimix analyzer, and since I was mixing my own gas, I needed to have one of my own, and I use it every time I make either nitrox or trimix in my home area.

I do not take it with me on recreational dive trips, though. I still rely on the supplier to have an analyzer. I just spent two months in Florida, and I had my trimix analyzer with me. I got my nitrox for my recreational diving from one operation and used another for the the trimix. In both cases, I used the ones at the shops while my analyzer stayed in my closet in my condo.

Now, there is no reason to be like me, but a lot of people do it that way. I have rarely seen anyone pull out a personal nitrox analyzer at a recreational diving location.

 

[DiveNav]

NitroxBuddy2
(coming very soon to a dealer near you)
(and it can be operated - and calibrated - without a smartphone)​