GB/T 11200.3-2008 Focused on high-purity sodiumhydrate test, Part 3 of which stipulates the determination of calcium content by flame atomic absorption method. In the production and application field of high-purity sodiumhydrate, calcium content affects product purity and performance. The standard elaborates the operation process and provides unified specifications for relevant personnel. With this method, calcium content can be accurately determined, helping manufacturers control product mass, meet the needs of industries such as electronics and chemicals that require high purity of high-purity sodiumhydrate, and promote the high-mass development of high-purity sodiumhydrate industry.