ISO 3987:2024

This document describes a procedure for the determination of the mass percentage of sulfated ash from unused lubricating oils containing additives and from additive concentrates used in compounding. These additives usually contain one or more of the following metals: barium, calcium, magnesium, zinc, potassium, sodium and tin. The elements sulfur, phosphorus and chlorine can also be present in combined form. This document is also applicable to fatty acid methyl esters (FAME).
This test method is applicable to products having sulphated ash contents in the range mass fraction of 0,005 % to 25,00 %. Application of this procedure to sulfated ash levels below a mass fraction of 0,02 % is restricted to oil products containing ashless additives.
This document is not intended for the analysis of used engine oils containing lead, nor for the analysis of non-additive lubricating oils, for which ISO 6245 is suitable.