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Salt for salt spray testing

I'd like to have references for a salt which both meets ASTM B117-07 and ISO 9227.

Thank you in advance

Matthieu Spessotto
Plating Shop manager - Toulouse, France
March 2, 2009

There are inspectors that do not live in the real world. There are salts the will work well, but do not specifically say that they meet the spec. Using analytical reagent salt is cost prohibitive.

James Watts
- Navarre, Florida
March 6, 2009

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Matthieu

Salt that will work is sadly not good enough. If you are working to spec, the salt (and water) must be exactly as specified. You will be expected to have a certificate of conformity or analysis by a recognized laboratory.

I suggest that you contact the company who supplied the test chamber. They will have seen this problem many times and can supply either salt or a reliable supplier.

Geoff Smith
Hampshire, England
March 18, 2009

Hi, folks. I personally find this topic very funny and ironic because I remember when I was employed by the largest manufacturer of salt spray chambers many years ago, and the first customer called to ask if we could ship him saltwater. We were rolling on the floor laughing about how 2/3 of the earth is covered by ocean.

But times have changed so radically that the test solution needs to be made up with great precision from analytically pure materials these days. So here is the question: Is there any evidence whatsoever that it actually matters? In other words has any testing body ever shown that there is the tiniest variability in results induced by using a commercial salt vs. reagent grade? Or is this yet another example of throwing a fortune down a rat hole for precision without accuracy?

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
May 13, 2009

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I worked with 3 different salt spray cabinets, all from probably the largest MFG or at least one of the oldest. They could not give me a source of salt that totally complied with the spec. I bought sacks of salt that I think was from Morton and was listed as purified. We had a general certificate for it and it was really close, but not 100% exact. I do not remember what the missing element was. I got grief from a major OEM and my response to them was "you tell me where you buy your salt from, and I will buy from them also". That ended the discussion because as I found out what they used did not perfectly meet the spec and was a salt that I found less perfect than what I was using.
Has anything changed in the several years that I have been out of the loop?

James Watts
- Navarre, Florida
May 13, 2009

There are a couple of suppliers in the UK that release their salt against ASTM B117. I suspect that if you ask some of your local suppliers they will be able to direct you to a relatively local source for the material.

Brian Terry
Aerospace - Yeovil, Somerset, UK
May 18, 2009