A device has been developed for studying the effect of light on polymeric meterials used in conservation (i.e. consolidants, adhesives, resins). The light source, standard fluorescent tubes with polycarbonate UV filters, is intended to approximate the spectral emission and spatial distribution experienced by objects in museums. The paper explains the development of the apparatus and provides schematic diagrams. Also described are the techniques for measurement and results obtained for light intensity, spatial and spectral distribution of light, and absolute irradiated energy in watt/cm³. The usefulness of this apparatus is being evaluated with a study of the light stability of parylene. -- CAL