Tests were made for a quantitative decomposition of N₂O to N₂ and for the setting of a statistical equilibrium in mixtures with gaseous nitrogen of nonrandom distribution by emission spectrometric continuous-flow-measurements. Under high-frequency-discharge conditions a residence time of 0.5 seconds is enough for a quantitative decomposition. In this time the statistical balance in the mixture of N₂O and N₂ is reached. The determination of the relative ¹⁵N abundance in pure N₂O or N₂ gases or in mixtures of N₂O and N₂ in a continuous-flow-emissionspectrometer can directly be achieved.