Changing a tank from nitrox back to air?

[demarest652]

What do you have to do to go back to using air in a tank that has been used for nitrox?

 

[gotwake]

Nothing. But you may have to have the tank O2 cleaned before going back to a nitrox. It all depends on the way your LDS fills the tanks. If they use the partial fill method, the tanks need to be O2 cleaned when going back to nitrox

 

[bleeb]

Generally, empty it down to close to ambient so that you know it's full of 21% after being refilled, rather than some richer mixture, possibly unknown. Depending on knowledge, equipment, skill level and risk tolerance, emptying may be optional, but in general is the commonly recommended practice. It can be emptied just before filling, which also helps keep the inside of the tank from getting contaminated. The usual care in (quickly) emptying a tank should be taken. There's no special cleaning or parts needed, if that's what you're wondering.

 

[Peter_C]

I have "heard" some shops will not fill a tank that has a nitrox band with air.

 

[rstofer]

I have "heard" some shops will not fill a tank that has a nitrox band with air.

This is probably true if they don't have 'Safe Air' as it is called around here. Safe Air is the air used to blend Nitrox when using partial pressure blending. It is clean and oxygen compatible.

Nasty dive air from the shop that doesn't do Nitrox will add contaminants to the tank and the tank will need to be oxygen cleaned before reverting to Nitrox use. The shop may insist that the Nitrox band and the Oxygen Clean label be removed. That is the proper thing to do because the Nitrox blender depends on the tank being clean when he puts in pure Oxygen.

Virtually all of my tanks have Nitrox bands and are oxygen clean. However, they may not have Nitrox but Safe Air. I just fill out the MOD info for air just as though it was Nitrox. I suppose I should check the O2 concentration when a tank is filled with Safe Air but I haven't. Maybe when I get my own tester.

Richard

 

[Peter_C]

This is probably true if they don't have 'Safe Air' as it is called around here. Safe Air is the air used to blend Nitrox when using partial pressure blending. It is clean and oxygen compatible.

Nasty dive air from the shop that doesn't do Nitrox will add contaminants to the tank and the tank will need to be oxygen cleaned before reverting to Nitrox use. The shop may insist that the Nitrox band and the Oxygen Clean label be removed. That is the proper thing to do because the Nitrox blender depends on the tank being clean when he puts in pure Oxygen.

Virtually all of my tanks have Nitrox bands and are oxygen clean. However, they may not have Nitrox but Safe Air. I just fill out the MOD info for air just as though it was Nitrox. I suppose I should check the O2 concentration when a tank is filled with Safe Air but I haven't. Maybe when I get my own tester.

Richard

I would agree that could be one reason, but what is the whole purpose of the sticker in the first place? Isn't it to keep an unsuspecting person from ox-toxing on enriched air because it was not labeled? So couldn't the same thing be said for air being in a nitrox labeled tank? Someone might go right past their NDL's thinking they are on nitrox.

A good measure is to always test the tanks mixture that you are going to be using.

FWIW "Safe air" is also known as Hyper filtered air.

 

[The Kraken]

Fill it.

If the tank has a "NITROX" sticker on it, then the diver using the tank should check the gas in the tank before a dive to determine the O2 content of the gas.

the K

 

[The Kraken]

There ya go !!!

the K

 

[Jim Lapenta]

Don't you think he should do the ritual as well? I mean c'mon his instructor obviously did not go over it with him so we should at least tell him the truth! First of all you need to empty the tank inside the shop in front of the employee who will be filling it. Do this by setting it down and open the valve all the way. Do not point it at anyone they could ox-tox! This way he knows he's not mixing air with the voodoo gas. THen you pick up the tank and shake it upside down so he knows there's no oxygen left in it. While shaking the tank chant- out, out damn trox! I banish thee from this vessel! Then set it down and walk around it 3 times while holding your index finger on the valve and finally look at everyone and crow like a rooster three times. THEN you can put air in a nitrox tank.

 

[The Kraken]

Don't you think he should do the ritual as well? I mean c'mon his instructor obviously did not go over it with him so we should at least tell him the truth! First of all you need to empty the tank inside the shop in front of the employee who will be filling it. Do this by setting it down and open the valve all the way. Do not point it at anyone they could ox-tox! This way he knows he's not mixing air with the voodoo gas. THen you pick up the tank and shake it upside down so he knows there's no oxygen left in it. While shaking the tank chant- out, out damn trox! I banish thee from this vessel! Then set it down and walk around it 3 times while holding your index finger on the valve and finally look at everyone and crow like a rooster three times. THEN you can put air in a nitrox tank.

That's better than the picture Uncle Pug posted of the non-O2 cleaned snorkel!!!!


I LOVE IT !!!!!

the K