This International Standard specifies a method for the determination of the chlorine and bromine content of liquid petroleum products, synthetic oils and fluids, and additives for petroleum products (including used oils) that are soluble in organic solvents of negligible or accurately known chlorine/bromine content. The method is applicable to products or additives having chlorine contents in the range 0,000 5 % (m/m) to 0,100 0 % (m/m), and bromine contents in the range 0,001 0 % (m/m) to 0,100 0 % (m/m). Other elements do not generally interfere, although lead may interfere at contents above 0,150 0 % (m/m) (see note 2). NOTE 1 For the purposes of this International Standard, the term “% (m/m)” is used to represent the mass fraction of a material. NOTE 2 Used lubricants may pose particular problems due to the range of potentially interfering elements at relatively high concentrations. For used lubricants generally, the lower limit of sensitivity may be 0,005 0 % (m/m) even when the provisions of the last paragraph of 9.3 are applied.