This standard refers to the testing of the chemical stability of coloring powders, by cold investigation of the acidity of a sample, placed in an alcoholic solution of a very sensitive indicator: p-dimethyl-amino-azobenzene. P-dimethyl-am?noazobenzene, in alcoholic solution, has a yellow color that turns red due to the action of acids, this dye fixing to the gunpowder as a coloring matter. When the color continues to be lemon-yellow, the gunpowder is neutral and if it becomes red, more or less intense, after a certain time, the acidity appears, which means that the gunpowder is in a state of decomposition.