Pablo got a MSDS question for you

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Nov 25, 2003
The Tropics of Antartica
I remember you telling in a post that you wrote MSDS's in the past so..........

If a MSDS shows mixture for the CAS of the base oil does that mean it's not just one base oil in the formulation ? Effectively a mixture of one or more base oils ?
Let's assume three petroleum base oils are mentioned such as 647-blah-blah, etc.

In most cases, it means this is a mix of those base oils so as to arrive at a target viscosity. Each base oil might be a different viscosity so each separate base oil is mixed in proportion to get say 10.5 cSt. Oil A may be a 40 cSt paraffininc oil, oil B may be an 8 cSt parafinninc oil, and oil C might be a naphthenic base oil of 5 cSt to get a 5W30.

IN other cases, this might indicate that any number of base oils from different suppliers may be in the mix at any one time, due to supply/demand, pricing, etc.

See the Question of the Day topic, "Graff Chart."

[ May 18, 2004, 08:05 PM: Message edited by: MolaKule ]
Me not Pablo, but me can add to MolaKule's comments...

CAS numbers are unique to individual base chemicals and compounds, and various virgin base oils have differing CAS numbers. CAS numbers are not required on MSDSs. This GM tranny fluid MSDS (non-pdf format) lists three different lube oil CAS numbers:

So if you're seeing multiple CAS numbers, you can search what specific oil types those CAS numbers refer to. Unfortunately the percentage of each component does NOT have to be listed per federal law, so typically one sees only broad ranges (like ">60%") if even that.

Expanding on MolaKule's comment, one MSDS can actually cover several slight variations of motor oils:
How can I argue with the two answers that are correct but from different angles?

I can't, but I will add that there is some leeway given when the base oils have very similar toxicity a blend of similars can be very hidden...through in some very generic lingo, and what I have been saying it's best to reverse engineer a blend in some other method than the (silly) MSDS's (I know some that were very deceptively written)
It would be FUTILE to attempt to reverse engineer a fluid based on MSDS'.

Proprietary additive packages don't have to be listed is one case in point.
One thing I'd add is that as long as a component poses a health or physical (such as combustibility) hazard, it must be listed. There's no exception for proprietary compounds -- they must also be listed as ingredients -- but they may be listed under an anonymous name such as "proprietary lube oil," rather than something more specific like "heavy naphtha distillate, CAS #XXX-XXXXX." Other aspects of that proprietary compound must be revealed as well, such as chemical qualities, fire control, first aid, etc. For that matter, should a medical provider or a health & safety administrator request the identity of a proprietary compound, it MUST be revealed to that party, per federal law.

[ May 19, 2004, 04:29 PM: Message edited by: TC ]
So , again if the base oil is listed as mixture without CAS numbers , it is more than one base oil in the formulation . Blended basestocks of different CAS numbers w/o listing the CAS numbers . Correct ?

As in figuring out if or not a oil , thought to be entirely group II+ and nothing else mixed in for basestock has a MSDS showing mixture it's not entirely the base oil thought to be group II+ only ...... correct ?
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