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This paper concerns the flame extinguishing with the use of acoustic waves. A small laboratory stand allowing to generate acoustic waves in the horizontal direction was used for that purpose. The speaker extinction power and the acoustic extinction pressure were selected to quantify the process. Varying frequencies (30–50 Hz) burner powers (3.45-11.72 kW) and distances between the acoustic source and the flame (0.02–0.06 m) were investigated. It was shown that the lower the frequency is it is easier to extinguish the flame. It was also found that the fuel load has a minor impact on the extinction pressure. The results are supplemented with the visualisation of the flame behaviour under the influence of acoustic waves performed with the use of Schlieren apparatus. It was shown that the extinction is a result of cumulative effect of acoustic mean flow and oscillatory perturbations. [ABSTRACT FROM AUTHOR]