This Standard is a design and specification standard that covers metallic and solid polymer centrifugal pumps of horizontal, end suction single stage, centerline discharge design. This Standard includes dimensional interchageability requirements and certain design features to facilitate installation and maintenance and to enhance reliability and safety of B73.1 pumps. It is the intent of this Standard that pumps of the same standard dimension designation from all sources of supply shall be interchangeable with respect to mounting dimensions, size and location of suction and discharge nozzles, input shafts, baseplates, and foundation bolt holes. Maintenance and operation requirements are not included in this Standard. This Standard has been revised to include solid polymer pumps formerly covered under ASME B73.5.