This part of ISO 13909 specifies procedures and requirements for the design and establishment of mechanical samplers for the sampling of coal from moving streams and describes the methods of sampling used. It does not cover mechanical sampling from stationary lots which is dealt with in ISO 13909-3. Examples of calculations of the number of sub-lots and number of increments per sub-lot are given in annex A. Requirements for the evaluation of sampling equipment are given in annex B and information on the operation of mechanical samplers is given in annex C.