How much rust after hydro is acceptable?

[duckbill]

I'd be concerned that even after blowing out the tank, fine steel or rust particles will remain to be breathed into the lungs. I'd rather have some rust in a tank than have steel dust in my lungs.

Adam

The loose rust dust should be pretty well blown out. Besides, that's what the sintered filter is for. Any particles that get past that will be inconsequential.

 

[Delta_P]

I'd be concerned that even after blowing out the tank, fine steel or rust particles will remain to be breathed into the lungs. I'd rather have some rust in a tank than have steel dust in my lungs.

Adam

Dude, you do not want to see what ends up in the air stream when a compressor operator doesn't drain condensate properly and the mild steel fittings downstream of the filters start to rust. Bank bottle internals can be interesting at times too.

Hopefully it just gets absorbed through the lungs and contributes to your RDA for iron.

 

[Delta_P]

As a professional you should access to a copy of the MSDS (by law you have the right to know what you're working with). Would you post a copy so we can see proof that the rust inhibitor is non-toxic?

 

[knotical]

Following up on moinaman's reference in post #25 and Delta P's suggestion in post #33:

GMC has been in the business of selling equipment and materials for cylinder cleaning, among other things, for many years. They also have a reputation for providing solid information to the scuba industry. The rust inhibitor they recommend is dilute diethanolamine. See the discussion of "Compound O" on page 9 of the reference. They recommend wetting the interior of the cylinder with a dilute solution, and rinsing briefly to leave a trace, which

will halt flash rust and be dissipated during drying

The MSDS can be seen here: http://www.sciencelab.com/msds.php?msdsId=9923743
If you're not familiar with reading MSDS's it can appear scary, but note that diethanolamine is given a health hazard of 1, with 0 being "least severe hazard" and 4 being "most severe hazard". (see for example: The MSDS HyperGlossary: NFPA )

 

[Indian Valley Scuba]

Not to undercut all the emotions here in these responses, but seriously, unless you are planning to jet pure oxygen into these cylinders, what difference does a little flash rusting make in the big scheme of things?

And what was that concern about where the droplet of water ended at the end of the rusty streak?

Non-emotional responses encouraged!

 

[DevonDiver]

---

---

A ScubaBoard Staff Message...

Lets keep the discussion civil please. There's no need for personal remarks or insults in such a benign thread topic

---