This standard applies to the determination of lead content in sodium stannate, with a determination range of 0.0010% to 0.0030%. Methods After analyzing samples using aqua regia, the Flame Atomic Absorption Spectrometer (FAAS) was used to measure lead Absorbance at a wavelength of 283.3 nm in 10% aqua regia media. The standard specifies in detail the preparation of reagents, the conditions of use of the instrument and the analysis procedures to ensure the accuracy and repeatability of measurement. It is suitable for the detection of lead content in sodium stannate in scientific research and industrial analysis.