Optical emission quantometry (OEQ) has a direct approach in the analytical quality control/assurance at metallurgical works. It became an inevitable analytical tool for them. This is mainly due to rapid and reproduceable results with economic aspects of analysis. Although OE quantometers, themselves are much expensive, but analysis by them are quite cheaper in comparisons with other techniques. Herein, the analyses are commercially very economical and rapid that hundreds of samples (For more than 25 elements in single spark) can be tested per shift and Spectral Laboratory can work as Spectral analytical factory. Excitation of samples with the additional energy to a nucleus of an atom or molecule, transferring it from its ground state to higher energy level, resulted certain critical spectrov. Techniques of excitation varies with the nature and quantity of samples. Past decades have much developed the commonly employed excitation sources, for major area of Spectral analysis.