NITROX and Luxfer tanks

[tedwhiteva]

From the Luxfer web site:

"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."

I guess that means that the "Certified to 40%" stickers are no longer valid on their tanks. Anyone know any different?

 

[Scottri]

It depends on what method they used to fill the tanks. I 02 clean all of the tanks I intend to use for Nitrox. As far as Luxfer, it doesn't make a difference what brand it is.

Scott

 

[ReefGuy]

Agreed. It never hurts to clean new tanks.

 

[Spratman]

So, would it be reasonable then to buy a used tank for air and a new tank for Nitrox? I was planning to do this, but.....

Jack

 

[jonnythan]

I think you will find that no one filling tanks probably knows or carse what Luxfer says on the subject, and will fill any tank with continuous or banked nitrox up to 40%.

 

[wedivebc]

From the Luxfer web site:

"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."

I guess that means that the "Certified to 40%" stickers are no longer valid on their tanks. Anyone know any different?

The 40% "standard" adopted by NOAA and by the scuba industry in general contradict the Compressed Gas Association regulation that states that concentrations above 23.5% O2 must be treated as an oxygen enriched mixture.
CGA probably has a lot more clout than NOAA when it comes to this issue.

 

[padiscubapro]

I think you will find that no one filling tanks probably knows or carse what Luxfer says on the subject, and will fill any tank with continuous or banked nitrox up to 40%.

What it also means is that IF there is any problem, and the LDS wasn't following luxfer (manufacturer) recommendations, the LDS is SOL and will probably be on the bag for any cost involved in a lawsuit.. Their liability insurance wount be worh the paper its printed on..


Catalina also has similiar rules as well as thermo valves.. The people at most risk are the owners of the LDS, and believe me if there is a potential for money a good lawyer will find a way to prove a "history of disregard for the rules"..

Most of the agencies who Push this so called 40% rule have a way out of the liability issue there is a little clause that are in most instructor procedures that they are supposed to pass on, usually with any mention of the 40% rule there is an added saying you must follow manufacturer recommendations.. so guess who else gets dragged into the lawsuit if they didn't teach this...

 

[Doc Intrepid]

So, would it be reasonable then to buy a used tank for air and a new tank for Nitrox? I was planning to do this, but...

Jack,

Unless the tank has been abused, used tanks are fine to use with nitrox. You can O2 clean any tank. Literally, you yourself can, if you know how, or you can have it done at the shop. You don't need to buy a new tank for nitrox.

(One of the things you may want to do is take a blenders class, you'll learn to clean tanks and mix your own nitrox.)

Doc

 

[Leadking]

All of our new Luxfer cylinders are being shipped with Luxfer's green warning label which states the cylinder is oxygen clean.

 

[Henryville]

The issue is how the tank will be filled.

There are still plenty of shops filling nitrox using partial pressure blending. Doing so, you hit the valve and tank with high-pressure 100% oxygen, then top off with oxygen compatible air. You can be well below 40% when you finish a nitrox fill, but still expose the valve and tank to high-concentration conditions. Luxfer's advice will cover you for this filling method, and of course also for banked nitrox.

However, bear in mind that if you fill the tank with grade "E" air (most common) or banked nitrox that is not made from de-nitrogenating hyper-clean (Oxygen compatible) air, your valve and tank are defacto no longer oxygen clean and technically should not be taken to a shop that partial pressure blends until they have been re-cleaned.

An instructor published this account of an O2 flash on decostop, it illustrates what could happen and why you would want to be O2 clean for partial pressure blending, even though she was using 100% O2 the same principle applies.

http://www.thedecostop.com/forums/showthread.php?t=568&highlight=Flash