This European Standard gives guidance on the criteria and the fundamental operation procedure governing the spark optical emission spectral analysis (S OES) of metal samples, beginning with sampling, through sample preparation to reporting the test, as well as the requirements of the whole spark source spectrometric procedure which shall be fulfilled with respect to:- observance of the agreed precision and trueness [ISO 3534 1, ISO 5725-1] of the analytical results with reference to the agreed sample or sample area;- traceability of the analytical results to the international base units - mass (kg) and amount of substance (mol);- proof of agreement between