Inductively coupled plasma optical emission spectrometry (ICP-OES) is a powerful method for the analysis of brines, used for the electrolysis of alkaline chlorides. ICP-OES allows the direct simultaneous determination of trace elements in 200 g/L NaCl solutions . Using the SPECTROGREEN with dual side-on plasma observation, which provides an average factor 1.5 higher sensitivity in the matrix compared to single radial view, the required sensitivity for Ca, Mg, Sr, Ba, Al, Fe, Cu, Ni, Hg and P is can even more easily achieved to control the high purity specifications for NaCl. The report includes the line selection, detection limits and studies on precision and accuracy.