Name that contaminant

[*dave*]

These are pics of valves removed from cylinders for VIS. They had only been filled at two locations, so the source of contamination was pretty easy to track. I assume it's filtration medium, but unsure of its exact composition. It's extremely fine and has no taste or odor.

What is it?

 

[Teamcasa]

aluminum oxide - If it's an aluminum tank.

 

[sink-er-swim]

Is it also building up in the divers regulators?

 

[Scared Silly]

I am going to say that if the cylinders are AL that they got water in them causing an aluminum oxide slurry that found it's way to the valves.

 

[*dave*]

Cylinders are steel and there is no detectable contamination of the regs. I'm speculating that the deposit was created during the fill and it adhered to the walls and valve. It wipes away easily, but doesn't just fall off without some help. Aluminum Oxide doesn't wipe off like this and isn't nearly as fine.

 

[HowardE]

were these tanks shipped across any international borders?

 

[*dave*]

I asked if they'd been diving Colombia lately, but that was not the case. The powder is tasteless.

 

[UnderSeaBumbleBee]

I asked if they'd been diving Columbia lately, but that was not the case. The powder is tasteless.

How do you feel after you taste the tasteless powder?

 

[HowardE]

I asked if they'd been diving Columbia lately, but that was not the case. The powder is tasteless.

Yeah... that was probably a good idea.

 

[*dave*]

I felt kinda ornery after tasting it.