This part of EN ISO 6326 specifies a method for the determination of total sulfur in natural gas. The method is applicable to gases with sulfur contents between 0,5 mg/m3 and 1.000 mg/m3. With a total sulfur content of more than 0,1 mg sulfur in the absorption solution, visual titration with an indicator can be chosen, whereas for lower contents turbidimetric titration is preferable.