The paper presents the results of the developed unique technique application related to the solution of one of the most important metallurgical industry tasks -determination and control of the impurities content in metals and alloys in factory conditions using emission spectrometers of domestic production. This method, by solving the problems of accurate measurement of plasma background radiation, taking into account the influence of "third" elements, makes it possible to calibrate the spectrometers in the area of small impurity content using two standard samples.