This standard applies to the determination of lead content in cobalt oxalate, with a determination range of 0.001% to 0.01%. The method mainly uses graphite furnace AtomicAbsorption Spectroscopy in dilute nitric acid medium after analyzing the sample, measuring the Absorbance of lead at a wavelength of 283.3 nm, applying Zeeman effect to deduct background interference, and finally calculating the lead content according to the standard Linear dispersion method. The standard also specifies the reagents, equipment and determination steps required for the experiment to ensure the accuracy and repeatability of the measurement.