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I finally found the reference from the CGA regarding my earlier query.What  I
have found is a quote:
SAFETY BULLETIN
Compressed Gas Association, Inc. 1725 Jefferson Davis Hwy.  Arlington, VA
22202-4100
SB-7--1992
RUPTURE OF OXYGON CYLINDERS IN THE DIVING INDUSTRY

There have been a number of incidents wherein oxygen cylinders have failed
violently after having been used in offshore diving operations.  Member
compaines of the Compressed Gas Association have studied  this hazardas
problem and have determined that the cause of the cylinder ruptures has been
the mishandling of the oxygen cylinders by the users, in that they have
allowed sea water to flow back into the cylinders after the oxygen in the
cylinders has been depleted.  The metallurgical test portion of these studies
shows that sea water in a standard DOT/CTC/TC 3A or 3AA oxygen cylinder will
cause exttremely rapid corrosion to the extent that THE CYLINDER WILL FAIL
VIOLENTLY WITHIN 30 TO 60 DAYS (depending on the oxygen pressure in the
cylinder)

Industrial gas companies have attempted to provide additional operating
procedures in their fillin operations so as to ascertain the presence of sea
water in returned cylinders, since the hazard is not only associated with the
user but also with the producer who transports, handles, and refills the
cylinders.  These special additional procedures have included weighing the
cylinders individually against their tare weights, analyzing the residual
contents of the cylinders for the presence of water, and inverting each
cylinder before discharging the residual product.

It has further been recognized by these industrial gas companies that if  the
users would follow a few simple procedures whil using oxygen cylinders, it
would be of tremendous assistance in solving this hazardous problem.  The
following therefore are recomendations to the offshore diving industry which
will assist the industrial gas industry in ascertaining the potential of
hazardous corrosion in oxygen cylinders:
(1)  If at all possible do not attach an oxygen cylinder to a submersible, or
allow an oxygen cylinder to be submerged.  If the user(s) operations do not
allow This recomendation to be followed, and when the submerged cylinder has
been emptied, paint SUBMERGED  in large letters down the side of the
cylinder.
(2)  If a cylinder or bank of cylinders are kept on the surface and are used
to supply oxygen to an underwater operation, do not allow the residual
pressure in the cylinders or the bank of cylinders as they are emptied to
fall below two times the equivalent sea water pressure at the depth where
oxygen is used.
(3)  Never transfill oxygen(or any other compressed gas) from one cylinder or
bank of cylinders to another cylinder or bank of cylinders without permission
of the owner of the cylinder(s).  US and Canadian regulations (49CFR, Par.
173.301 (b) in the United States and equivalent Transport Canada regulaions)
prohibit the shipment of comprressed gases if the cylindr(s) has(have) been
filled without the owners consent.

**CGA GRANTS PERMISSION TO REPRODUCE THIS TECHNICAL BULLETIN**

I've personally seen a fairly highly thought of tech shop poor water out of
aluminum bottles used for O2 deco and nitrox.....hopefully from compressor
condensate as the water dove in was salt.
Lets be careful out there.
Have a pleasant....
Bill Pilicer
PS the bulletin is current and has not been updated according to the CGA.  

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