This document specifies the procedure and gives guidance for structural design of buried thermoplastics piping systems under various conditions of loading for nonpressure application. This document can be used for pressure piping systems before applying operating pressure. NOTE 1 Piping systems for gaseous fluids, district heating and industrial applications are excluded. This document is applicable to all solid and structured wall thermoplastics piping systems covered by an EN standard developed by CEN TC 155. Operating conditions for nonpressure piping systems as defined in EN 476 shall be respected. This document gives guidance for structural design by either validated field experience or calculation.