BS 4825-5:1991 Stainless steel tubes and fittings for the food industry and other hygienic applications. Specification for recessed ring joint type couplings
Specifies dimensions, tolerances, surface finish, hygienic, assembly and materials requirements for welded and expanded type male parts and liners, nuts and seals for recessed ring joint type fittings for use with stainless steel tubes specified in BS 4825-1.