1.1 This International Standard covers the Class I (most severe) requirements for centrifugal pumps used in various industries. It consists of a basic text covering general requirements. The technical requirements refer only to the pump unit. Storage pumps are not included in this International Standard. A separate standard will be issued by IEC. 1.2 This International Standard includes design features concerned with installation, maintenance and safety of such pumps, including baseplate, coupling and auxiliary piping. c 1.3 Where this International Standard specification has been called for: a) and requires a specific design feature, alternative designs may be offered which meet the intent of this International Standard, provided that the alternative is described in detail; b) pumps not complying with all requirements of this International Standard may be offered for consideration, provided that all deviations are stated.