This specification covers three types of mortar cement for use where mortar for masonry is required. Mortar cements are classified as Type N, S, or M, according to the prescribed physical requirements. Mortar cement shall conform to the prescribed requirements such as fineness, autoclave expansion, time of setting, compressive strength, flexural bond strength, air content of mortar, and water retention. Test specimens shall undergo molding and storage before conducting the procedures in the required test methods.