This document is a sectional specification relating to printed board assemblies of assessed quality which meet the criteria for a modular electronic unit as defined in the generic specification EN 160000. It applies to both custom built products and to standard catalogue items and defines the characteristics to be assessed and the test methods to be used for capability approval, for quality conformance inspection (lot-by-lot) and maintenance of approval. Acceptance criteria for specific printed board assemblies will be given in the relevant detail specifications in accordance with blank detail specification EN 160101.