This part of ISO 15117 sets out methods for the measurement of the flow properties of coal, primarily for the design of bins and chutes. It also provides some guidance on the presentation of these data for analysis and design. This part of ISO 15117 consists of a bulk density test and a yield locus test giving information on material flow properties. It also describes a further test, called the wall yield locus, which measures the friction between coal and bin wall material. Although this part of ISO 15117 is nominally for coal, the principles and apparatus may be used for coke and other semi-cohesive particulate materials where a knowledge of flow properties is required.