This part of ISO 8655 specifies – metrological requirements, – maximum permissible errors, – requirements for marking and – information to be provided for users, for dispensers. It applies to dispensers with nominal volumes from 1 μl up to 200 ml, designed to deliver their volume (Ex). NOTE – General requirements and definitions of terms for piston-operated volumetric apparatus are given in ISO 8655-1. The gravimetric reference measurement procedure for the determination of volume is given in ISO 8655-6. The photometric reference measurement procedure for the determination of volume is given in ISO 8655-8. Alternative methods for the determination of volume are described in ISO 8655-7. For safety requirements of electrically powered dispensers, see regional or national safety standards.