Denied Air Fill Due to Not Safe Air Cert

[Shcubasteve]

ANDI also requires O2 cleaning for any mixtures above 23.5%.
What is SafeAir?

So does Luxfer:

"..., the main thing to remember concerning Luxfer scuba cylinders is that when you fill a cylinder with an oxygen concentration of 23.5% or more, that cylinder must be specially cleaned for oxygen service as though it contained 100% oxygen."

and the US navy, NASA and the CGA.

Its amazing how much misinformation exists about EANx, and filling and handling cylinders. The biggest is the so called 40% 'rule' that doesn't actually exist.

Heres another from interesting fact from Catalina: that most fill station operators are unaware of

"The U.S DOT has interpreted its regulations stating that DOT-3AL (aluminum) SCUBA cannot be charged with oxygen enriched air to a service pressure greater than 3000psi. Thus, Catalina Cylinders 3300psi compact SCUBA cylinders cannot be charged with oxygen enriched air as mandated by the DOT."

 

[deepstops]

So does Luxfer:

"..., the main thing to remember concerning Luxfer scuba cylinders is that when you fill a cylinder with an oxygen concentration of 23.5% or more, that cylinder must be specially cleaned for oxygen service as though it contained 100% oxygen."

and the US navy, NASA and the CGA.

Its amazing how much misinformation exists about EANx, and filling and handling cylinders. The biggest is the so called 40% 'rule' that doesn't actually exist.

Heres another from interesting fact from Catalina: that most fill station operators are unaware of

"The U.S DOT has interpreted its regulations stating that DOT-3AL (aluminum) SCUBA cannot be charged with oxygen enriched air to a service pressure greater than 3000psi. Thus, Catalina Cylinders 3300psi compact SCUBA cylinders cannot be charged with oxygen enriched air as mandated by the DOT."

Actually, I'm very aware of the 23.5% rule (originating from CGA). There are a lot folks that like to use that "rule" because it offers the best coverage of their ass in a liability lawsuit. That being said, I'm not seeing a bunch of uncleaned tanks that "done blowed up" while getting filled with premix up to 40%......

 

[Thalassamania]

It's basically horse pucky ... Rutkowski and Wells' tests went well in excess of 40%, which was what they stepped back to, just to be sure.

 

[Graeme Tolton]

You just need to say "Thank you for saving my life. Goodbye." You cannot fix ignorant people. It comes down to some shops want to make their own rules... and they have the right to. It is their compressor. However, you don't have to get your fills there.

 

[padiscubapro]

The term "SafeAir" is American Nitrox Divers International's (ANDI) registered trademark for nitrox blends (including 21%) mixed with oxygen compatible air. ANDI asserts that their standards for air purity are higher than those of other agencies. My guess is that the shop was an ANDI shop and was trying to sell you some expensive stickers. I can't see any way that properly O2 cleaned tanks (without the SafeAir sticker) would filter back into the mixing system to contaminate their equipment.

The ANDI Enriched Air Mixtures manual, which is pretty good in many respects, is full of cute little phrases like "Remember, it may be Nitrox but if is not ANDI, it's not SafeAir." (The typo is theirs, not mine.) Kind of reminds me of a textbook for an X-ray technician training course I was involved in printing many years ago, which had a cartoon character called the Rad Man, who was always popping up saying things like "Remember, the gonads you save may be your own!"

Those stickers are pretty cheap, in fact I sell them to my customers at my cost (If I take my time into account I lose money) so I definately don't make any money there.. They get changed EVERY VIP as they SHOULD.. To do a proper VIP the oustside of the tank is also supposed to be carefully inspected, so ALL stickers are supposed to be removed... If you cant see under the sticker you cant see hidden issues..

How a tank can contaminate the fill station or other tanks is easy.. If the individual whips are not fitted with one way valves (most operators do not have this) a tank with a pressure higher than another tank on the manifold (this assumes you are filling more than one tank at a time) or if the pressure of the cylinder to be filled is higher than the current pressure at the whip or manifold it will back feed..

Personally I only protect my Banks and my booster loop as 1 way valves can instill a false sense of safety and being ANAL is a good thing in this case..

And YES ANDI's mandated gas standards are higher than the minimum required by any of the other agencies.. ANDI has always been anal about its gas quality and enforces it (otehrs may have standards but they are rarely enforced).. The tank doesnt need a safeair VIP must it must state on the VIP that its o2 clean not just "nitrox ready".. also if you look at the ANDI stickers they go one step further, they indicate all tests that were done at VIP.. O2 cleanliness of tank & valve, whether or not valve was rebuilt, if eddy current testing was performeded ect..

I have no problems filling a non o2 clean tank with air, but I make sure I take precautions so that the possibility of contamination to my system is prevented.. I wount fill "nitrox" into any cylinder that is not o2 clean whether its from my banks (I have over 20k cuft of various banked gasses) or I am PP blending...

 

[Thalassamania]

Why would you not fill a "non-O2 clean" tank from banked 32%?

 

[Shcubasteve]

Why would you not fill a "non-O2 clean" tank from banked 32%?

I bet its because he is abiding by his training agency's policy plus the manufacturer's recommendations and standards set by CGA NAVY, OSHA ect.

 

[Thalassamania]

Yet the very people who developed EAN, the experts, will tell you that's crap. It's self-serving, ring the register claptrap.

 

[padiscubapro]

Why would you not fill a "non-O2 clean" tank from banked 32%?

for ANY shops insurance they need to follow the guidleines of their agancies and the recognized experts..

in this case the experts are

The valve and tank manufacturers
CGA (for the US)
US NAVY and NOAA..

If there is an accident a good lawyer will fry you if you violate one of these groups recommendations..

The above is also why most shops enforce the strict labeling of Nitrox tanks with wraps or painted lettering since its specifically stated in the NOAA manual.. The simple MOD rating for NITROX tanks doesnt meet these guidlines and could void your insurance.. BTW there are no official guidelines for tanks with other gases like trimix..

AND if you think high pressure 32% is safe in all conditions, I have a picture of a compressor that blew up making 32% (I don't rember if it was continuous blending or NITROX stick)

Thirdly an O2 fire is not the big concern here its really that of INCOMPLETE combustion.. a "flash" fire can happen at these "normal" concentrations (this usually can only happen with fast pressurization when opening the valve).. There will generally be no outward signs.. what happens is that any contaminates on the valve or regulator (usuall hydrocarbon deposit like oil) will combust generating alot of CO... This is bad and generally undectable...

 

[DaleC]

Padiscubapro,

If one of your customers gets a fill somewhere else do you insist on O2 cleaning their tank again before you will fill with banked 32%?