7. Other features

Evaporation loss

The test can be carried out in the presence or absence of an air current, according to a specified method.

Residual carbon

When oil is heated in a crucible, under specific conditions and away from any flame, the oil vapors escape and, after a certain time, a so-called "residual coke" remains in the crucible, the size and appearance of which is an interesting characteristic of hydraulic fluid.