This standard applies to the determination of calcium content in potassium fluorotitanate by flame atomic absorption spectroscopy (AAS), the determination range is not more than 0.5%. Methods The sample was analyzed by nitric acid and perchloric acid, and the pH value was adjusted by ammonia to separate titanium. The calcium content was determined at a wavelength of 422.7 nm. The standard includes detailed instructions on reagent preparation, instrumentation and operation procedures to ensure the accuracy and precision of the determination.