This specification covers the manufacture and purchase requirements of products used for the assembly and construction of precast reinforced concrete manholes used in sewer and water works. Part I@ Sections 1 through 11@ of this specification presents general requirements and requirements that are common to each precast concrete product covered by this specification. Note 1 - Future products will be included in Part II in a future revision of this specification. The values stated in SI units are to be regarded as the standard. A complete companion specification to M 199M@ M 199@ is available for use with inch-pound units. Note 2 - This specification is a manufacturing and purchase specification only@ and does not include requirements for backfill@ or the relationship between field load conditions and the strength requirements of the manhole products and appurtenances. Experience has shown@ however@ that the successful performance of this product depends upon the proper selection of the product strength@ type of foundation and backfill@ and care in the field installation of the manhole products and connecting pipes. The owner of the project for which these products are specified herein is cautioned to require inspection at the construction site.