This part of ISO8655 specifies—metrological requirements,—maximum permissible errors,—requirements for marking and—information to be provided for users,for air-displacement (typeA) and positive-displacement (typeD) single-channel and multi-channel piston pipettes,complete with their selected tip(s) and any other essential, consumable parts, designed to deliver their specifiednominal volume (Ex).NOTEGeneral requirements and definitions of terms of piston-operated volumetric apparatus are given in ISO8655-1.Conformity testing (type evaluation) of piston-operated volumetric apparatus is given in ISO8655-6. Alternative test methods suchas photometric and titrimetric methods will be the subject of a future Part7 to ISO8655. For all other tests (e.g. quality assuranceby the supplier, analytical and measuring equipment quality assurance by the user) see ISO8655-6 or alternative test methods.For safety requirements of electrically powered piston pipettes, see IEC61010-1.