1.1 This specification covers steel sheet used in the manufacture of corrugated steel pipe for storm sewers, culverts, drains, and similar uses. The sheet is metallic coated by the hot-dip process. Material for this use is furnished in coils, flat in cut lengths, and corrugated in cut lengths. Many metallic coated materials are covered in this material specification. Users must determine which product best serves their needs. Five different metallic coatings are included: 1.1.1 Zinc-coated (galvanized), 1.1.2 Zinc-5 % aluminum-Mischmetal (Zn-5Al-MM) alloy coated, 1.1.3 55 % aluminum-zinc (55Al-Zn) alloy coated, 1.1.4 Aluminum-coated Type 2 (aluminized Type 2), and 1.1.5 Aluminum-coated Type 1 (aluminized Type 1). 1.2 Zinc-coated sheet is available in two coating weights [masses]. Other metallic coatings are available in one coating weight [mass] only. 1.3 The values stated in either inch-pound units or SI units are to be regarded separately as the standard. Within the text, the SI units are shown in brackets. The values stated in each system are not equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.