Cancels and replaces ISO 1328 (1975). Establishes a system of accuracy relevant to corresponding flanks of individual cylindrical involute gears. Specifies appropriate definitions for gear tooth accuracy terms, the structure of the gear accuracy system and the allowable values of pitch deviations, total profile deviations and total helix deviations. Applies only to each element of a toothed wheel taken individually. Does not cover gear pairs as such.