Hi O2 mix 1st stage and equipment

[dandrian]

Why not ?

(assuming of course that the air is clean)

Ok I guess maybe need to understand the levels and process of air cleaning. I will admit that I am in no way a gas blender but I have the understand that the filtering process for air is different and not a regulated as nitrox mixtures. You can't always assume that you are getting nitrox quality filtering with regular air fills can you??

Also just for the info, I fill some of my air tanks off of my SCBA compressor at the fire station. The compressor is rated for scuba fills, Group E I believe, and I was told that has as much to do with the amount of moisture that is allowed in the air. I was also under the impression that the air from this compressor does have a different filtering process than at a mixed air facility and I can not interchange(or at least I don't) these tanks. I keep separate tanks for the dive team as well as a regulator that is only used for air.

If I am misinformed about this, please let me know. I would like to understand this better as it is obvious I have a different point of view than others.

Thanks

 

[in_cavediver]

Ok I guess what I was trying to say that as soon as you use an O2 clean regulator with air, then it is not O2 clean anymore. Yes, it can be O2 cleaned again, but I took that the original poster was talking about using 100% O2. Maybe I misunderstood what he was looking for. Some people use O2 clean to describe regulators used for nitrox. To me O2 clean and nitrox clean are two different things. A nitrox clean regulator is used with air all the time. Most regs come out of the box with 40% nitrox clean. An O2 clean regulator is on an O2 content greater than 40% and sometimes even 100% like on a deco bottle.

I think the real jist behind all of the 02 clean this and that until it touches the not O2 clean this or that has to due with the accumulation of contaminants. All scuba air should be either grade E or modified grade E (suitable for PP blending nitrox). In theory, the modifed grade E air will provide less accumulation of contanimants between cleanings. Realize, there will ALWAYS be some accumulation of contaminants no matter what air or O2 you hook up. Its inevitable if for no other reason than the attachment and removal of the regulator from the tank valve will introduce contaminants. It is possible to use good old Grade E air as a top off in PP blending nitrox and can be done relatively safely if you keep the flow rates down.

That said, I tend to dedicate a reg to my O2 bottle so I don't have to have it cleaned as often. I also dedicate a tank to nothing but pure O2 for the same reason. Do I have to, nope and if I really needed it, I'd use the tank/reg for other gases and then put it back to O2 service. I personally am close to paranoid about flow rates with O2. I belive it was the Jet Propulsion Lab that said they could light anything on fire with Pure O2 if they could get a high enough flow rate. With that, everything I do with O2 is slow and deliberate.