This standard specifies the requirements, test methods, inspection rules, marking, packaging, transportation and storage of the food additive tetrapotassium hexacyanoferrate. This standard applies to tetrapotassium hexacyanoferrate prepared by the reaction of cyanide with ferrous sulfate, potassium chloride, etc., or the reaction of tetrasodium hexacyanoferrate (sodium hexacyanoferrate) and potassium chloride. Tetrapotassium hexacyanoferrate is mainly used as an anti-caking agent in table salt.