The development of analytical procedures for the analysis of selected reactive process gases in order to use them in the production of semiconductors without sample preparation is the main task of the presented work. Different atomic spectrometric methods e.g. Electrothermal Atomic Absorption Spectrometry (ETAAS), Microwave Induced Plasma – Atomic Emission Spectrometry (MIP-AES), Non dispersive Atomic Fluorescence Spectrometry and Inductively Coupled Plasma – Atomic Emission Spectrometry (ICP-AES) have been used for the development of the procedures. The physico-chemical features of the matrix request a fitted sampling e.g. suitable, non corrosive material of the tubes and unions, and modified analytical system. The described ETAAS system with an automated sampling system allows the determination of Cu, Fe and Ni in gaseous HCl, Cl2, BCl3 and SiH2Cl2 without sample preparation. A comparison of calibration with standard aqueous solutions as well as standard additions and calibration with a gaseous standard has shown the negligible influence of the matrix on the calibration using the ETAAS system.