Ean 18 ???

[yak]

I just picked up a used OxySpy and installed a new sensor in it. I waited a few hours to let the sensor adjust (they recommend waiting 30 minutes). I calibrated it on air to 20.9 %, then I sampled one of my EAN tanks. I checked my log and last time I dove it with EAN it was 35%. I then refilled it with air once and dove it on my last dive of the season. The analyzer is registering that tank at 18.1 % .:huh: I left it overnight, then recalibrated it and I'm still reading 18.1.


I've tried my other two air tanks and both read 21%, so it seems to be working ok.I plan on stopping by the shop that fills my nitrox to compare with another analyzer. I can't see how a 35% mix with about 800psi can be refilled with 21% and end up at 18%?

 

[Averill]

Accidentally topped with trimix? :11:

 

[Thalassamania]

A NARTOX fill?

 

[do it easy]

Airgon? :11:

 

[Thalassamania]

Yea ... what I really wonder is what the other 82% is!!!!

 

[Carribeandiver]

would that be technically called UEAN? (Un Enriched Air Nitrox)

 

[Thalassamania]

would that be technically called UEAN? (Un Enriched Air Nitrox)

Lean Mix, Hypoxic Mix or NARTOX are the common terms.

 

[427Dave]

I have heard of steel tanks that have sit for a while have a lower % of O2 due to oxidation of the steel inside the tank. I have never verified it and it may just be a wives tale, but also a possibility.

 

[Rick Inman]

I would definatally put a HE analyzer on it. If you can't absolutely verify the mix, I drain the tank, take off the valve and blow the thing out before re-filling and breathing off it.

Let us know what you find out.

 

[matjo1]

If only one reads that way, you got a steel tank that's rusting on you. If it's both, your fills are not what you ordered or your sensor is bad