1.1 This specification covers the manufacture and purchase requirements of products used for assembly and construction of circular reinforced corrugated steel manholes used in sewer and water works. Products covered by this specification are not normally used for the conveyance of sanitary or industrial wastes. The steel sheet used in fabrication of the manhole structures has a protective metallic coating of zinc (galvanizing), aluminum, 55 % aluminum-zinc alloy, or zinc-5 % aluminum-mischmetal alloy, or a polymer pre-coating. 1.2 Part I, Sections 1 through 11, of this specification presents general requirements and requirements that are common to each corrugated steel product in the sections outlined in 1.3. 1.3 Part II of this specification presents specific requirements for each manhole product in the following section: Product Section Grade Rings 12 Manhole Structures 13 Base Section 14 Steps and Ladders 15 1.4 Steel sheet with zinc, aluminized or polymeric coating may be specified for the fabrication of the manhole structures. Manhole structures made from sheets with composite coatings are always furnished with an approved coating. Note 1: Pipe fabricated with polymeric coated sheet may be used for sanitary sewers and industrial applications. Note 2: This specification is a manufacturing specification and purchase specification only and does not include requirements for backfill, or the relationship between field load conditions. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.