Double Checking Information on Used C02 Tanks / Help Deciphering Stamps

[CGish]

About 7 or 8 years ago, the company I worked for did the demo work to clean up an old grocery store in a strip mall and prepare the space to be rented again. The owner told us to throw everything away - he didn't want any of it. Among the hanging wires, ceiling panels, and ruined fixtures were two CO2 cylinders. They were sitting next to the remains of the old soda fountain. Rather than toss them in the dumpster, I kept them (I had the owner's permission to do so). They have sat in the corner of my brewing area in two different homes since then. They are 27" tall with the protective cap around the valve, and approximately 8" wide.

I am looking at a kegging system and want to make sure I am not missing anything. All of my searches say these two cylinders can be used until empty and then they will need pressure tested before they can be refilled.

Is there anything I need to do / be aware of that I have missed in my searches?

Here are pictures and the stamping on each cylinder:

The first is an unpainted aluminum tank.
Its markings are:
CTC/DOT-3AL 1800 U1202232(I or l)UXFER12A91-20(UnknownMarking?)C02 TW24.1
Original Stamp: 3 A9/73 99
Original Stamp: CCE COKE
On the "Do Not Remove" tag: 9075, 9091, 9192, 0007

Pictures:

The second is painted red.
Its markings are:
DOT-3AL 1800 BB90063 CATALINA CLIFFDIV 03 Cl 99 20 C02 TC-3ALM124
Stamped: CCECINCI
On the "Do Not Remove" tag: 9149, 9194, 0089, & 0216

Pictures:

TL/DR:
Is there any thing I need to be aware of with these tanks before I use them?

Thank You,
Cody

 

[JONNYROTTEN]

Pretty sure the TW is "Tare weight" what it weighs empty 24.1 pounds..Throw it on a scale and see where your at.Everything else...no clue
I wouldn't be using 7 or 8 year old Co2 in my beer either.cheap to refill.After it gets recertified,if you can even do that,when you go in for a refill youll most likely have your tank swaped out.So after your first fill youll have a different tank anyway

 

[CA_Mouse]

The stamp on the unpainted one 3 99 is the certification date. I forget if it is 5 years or 7 years from that date to be recertified. Which would have been either 3/2004 or 3/2006. The red one isn't as clear, but appears to have the same certification date of 03 99.

 

[actech]

Pretty sure the TW is
I wouldn't be using 7 or 8 year old Co2 in my beer either.

Why not? Gas isnt going to go "bad" I've got a brand new and an even older tank. gotten same way, intercepted on way to dumpster. Was full, No idea when I'll need to refill that 20# tank. Local fire extinguisher company said they'd recertify for I think $25

 

[JONNYROTTEN]

Pretty sure the TW is
I wouldn't be using 7 or 8 year old Co2 in my beer either.

Why not? Gas isnt going to go "bad" I've got a brand new and an even older tank. gotten same way, intercepted on way to dumpster. Was full, No idea when I'll need to refill that 20# tank. Local fire extinguisher company said they'd recertify for I think $25

Nothing scientific.I read lots of posts where someone mentions "off tastes" and "maybe its your air" seems to come up a lot. Theres enough things to worry about getting right brewing.Using 8 year old gas from an unknown source isn't worth the risk,for me anyway...Co2 is cheap and a 20# tank wil last a long long time

 

[chickypad]

Why not? Gas isnt going to go "bad" I've got a brand new and an even older tank. gotten same way, intercepted on way to dumpster. Was full, No idea when I'll need to refill that 20# tank. Local fire extinguisher company said they'd recertify for I think $25

Agreed. I got my tank from a medical office closing up, was 10 yrs out of date and still half full. Use them up then see if you can find a place that will do exchanges without charging you a recert fee.