测定包括在酸性溶液中co还原，释放氧气，过氧水合物和高锰酸钾。由于洗衣粉的特殊性和过氧化物的相对稳定性，洗衣粉的溶解可能不完全，并可能导致氧气损失；通过采用适合于测定活性氧含量的特定溶解方法，这些缺点得以避免。该方法可用于测定过氧化物，例如过硼酸钠。

The determination consists in co-reduction, with liberation of oxygen, of the peroxyhydrate and potassium permanganate in an acid solution. Because of the specifity of washing powders and the relative stability of peroxyhydrates, the dissolution of washing powders is likely to be incomplete and may result in a loss of oxygen; these disadvantages have been avoited by adoption of a particular method of dissolution appropriate to the determination of active oxygen content. This method may be used for determing peroxyhydrates, for example sodium perborate.