EN 197-1 defines and gives the specifications of 27 distinct common cements, 7 sulfate resisting common cements as well as 3 distinct low early strength blastfurnace cements and 2 sulfate resisting low early strength blastfurnace cements and their constituents. The definition of each cement includes the proportions in which the constituents are to be combined to produce these distinct products in a range of nine strength classes. The definition also includes requirements which the constituents have to meet. It also includes mechanical, physical, and chemical requirements. Furthermore EN 197-1 states the conformity criteria and the related rules. Necessary durability requirements are also given. In addition to those sulfate resisting cements defined in the present document, other cements conforming either to EN 197-1 or to other standards, European or national, have been nationally demonstrated to have sulfate resisting properties. These cements which are listed in Annex B, are considered by different CEN Member countries as sulfate resisting within the limits of their territory. NOTE 1 In addition to the specified requirements, an exchange of additional information between the cement manufacturer and user can be helpful. The procedures for such an exchange are not within the scope of EN 197-1 but should be dealt with in accordance with national standards or regulations or can be agreed between the parties concerned. NOTE 2 The word "cement" in EN 197-1 is used to refer only to common cements unless otherwise specified.