This European Standard contains the methodology for measuring the dustiness of bulk solids which contain nano-objects or particles in the sub-micrometer range or which are released under repeatable and standard conditions and specifies the rotating drum method for this purpose. In addition, this European Standard specifies the choice of instruments and devices and the methods for calculating and presenting the results. The standard also contains instructions for evaluating and specifying the data. The methodology specified in this European Standard enables a) the measurement of the mass fraction of respirable, thoracic and inhalable dust, b) the measurement of the number-based dust index of respirable particles in the size range between approximately 10 nm and 1,000 nm, c) the measurement of the number-based emission rate of respirable particles in the size range between approximately 10 nm and 1,000 nm, d) the measurement of the number-based size distribution of the released aerosol in the size range between approximately 10 nm and 10 µm and e) the collection of released suspended matter in the respirable fraction for subsequent observations and analyzes by means of analytical electron microscopy. This European Standard applies to the testing of a large number of different bulk solids, including powders, granulates or pellets, which contain or release nano-objects or sub-micron particles in unbound, bound and uncoated and coated form. d) the measurement of the number-based size distribution of the released aerosol in the size range between approximately 10 nm and 10 µm and e) the collection of released suspended matter in the respirable fraction for subsequent observations and analyzes by means of analytical electron microscopy. This European Standard applies to the testing of a large number of different bulk solids, including powders, granulates or pellets, which contain or release nano-objects or sub-micron particles in unbound, bound and uncoated and coated form. d) the measurement of the number-based size distribution of the released aerosol in the size range between approximately 10 nm and 10 µm and e) the collection of released suspended matter in the respirable fraction for subsequent observations and analyzes by means of analytical electron microscopy. This European Standard applies to the testing of a large number of different bulk solids, including powders, granulates or pellets, which contain or release nano-objects or sub-micron particles in unbound, bound and uncoated and coated form.