What is a safe flash point? How is it tested?

The flash point of a lubricant is often considered an important used oil analysis parameter, particularly when it comes to personnel safety. Thermal systems in particular tend to have a high focus on the flash point, but what do the tests actually represent? Unlike properties like viscosity, the flash point is not inherently a property of the lubricant, rather it is defined by the test method used, so it is important to understand the common ASTM methods used to test flash point of oils.

[@LubricationExplained]

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[@MrSensible2]

I was never really that bothered about the flash point of oil. It was simply something you needed for writing the safety data sheet but that was about it.
I never looked to actually test it, but my gut feel is that the flash point of any fresh PCMO drops like a brick, the moment you put it in an engine & start using it. The reason is that you'll always get a bit of partially burnt gasoline getting past the rings especially when it's cold outside & you first fire up the engine. Having low tension rings & a GDI engine exacerbates this effect. Gasoline is incredibly light relative to base oil & even the tiniest amount entering the oil in your sump will have a major effect on flash point.

[@LubricationExplained]

Definitely true in PCMO. Flash point tends to be much more important in the industrial sector - particularly thermal oil systems such as in the pulp and paper or forestry industries.

[@Gchethan31]

IP 346 highly refined mineral oil. Can you please tell is this group III oil ?
Most of indian motorcycle oils mention this in materials safety data sheet.

[@chippyjohn1]

Another component I must consider as my oil will be exposed to an absolute atmosphere pressure of 15kpa on one project and as low as 1.5 kpa on another.

[@LubricationExplained]

If you have specific questions - [e-mail]

[@chippyjohn1]

@@LubricationExplained I have at least 100 questions. When I am closer to manufacturing I will pay you for input. Thanks for all the videos.

[@LubricationExplained]

@@chippyjohn1 No worries!

[@rolandotillit2867]

So is it helpful to use different tests to get a more clear understanding of the "true" flashpoint? Like different fingers pointing at the same thing.

[@LubricationExplained]

Not hugely. Main thing is probably to stick with one consistent test but to be aware that the trend is important rather than the absolute number. The problem is that he flash point in an application will be dependent on the system equipment, so there isn’t a one size fits all solution.

[@abd91fat]

MORE VISCOSITY IMPROVERS WILL DECREASE THE FLASH POINT ?
MOST OF ENGINE OILS BETWEEN 220c and 240c ... is the 20 degree difference a huge thing?

[@MrSensible2]

VI polymers have negligible impact on the flash point of an engine oil.

[@LubricationExplained]

Agree with Mr Sensible!

[@ston_jude_ed]

I googled safe flash tuning for cars 😂 I’m fine with this tho

[@LubricationExplained]

Hahahaha.