The purpose of the IOGP S-615 specification documents is to define a minimum common set of requirements for the procurement of centrifugal pumps in accordance with API Standards 610, 12th Edition, January 2021, Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries, applicable to these industries. The IOGP S-615 specification documents follow a common structure comprising a specification, also known as a technical requirements specification (TRS), a procurement data sheet (PDS), an information requirements specification (IRS) and a quality requirements specification (QRS). These four specification documents, together with the purchase order, define the overall technical specification for procurement.