This European Standard specifies requirements for roof lights made of plastic materials (e.g. GF-UP, PC, PMMA, PVC) with and without upstands made of e.g. GF-UP, PVC, steel, aluminium or wood for installation in roofs. These roof lights serve the purpose of lighting by means of daylight and of ventilating interior spaces by means of opening devices.This European Standard applies to roof lights with a rectangular or circular ground plan (see Figures 1 and 2), with an opening span (width) or diameter not larger than 2,5 m and an opening length not larger than 3,0 m in roof pitches up to 25°. This document does not cover roof lights which contribute to the lo