Specifies a method for determining the percentage by mass of a sprayed coating powder which is actually deposited on a standard test target then powder is sprayed at the target from a spray gun under standard conditions. the method is applicable to powders applied by corona charging or tribo charging. The method may be used to compare the deposition efficiency of different powders with the same gun of different guns with the same powder. This method should only be used for comparison when powders or guns are evaluated consecutively, as the influence of the environment and the equipment can vary significantly with time and location. The results are dependent on the following properties of the powder: a) chemical composition; b) density; c) particle size distribution; d) particle shape; e) flow properties of its mixture in air; f) moisture content and also on the test conditions, including: g) spray pattern produced by the gun; h) gun air pressure; i) gun voltage; j) gun polarity; k) air humidity