WRAP has announced positive results for a research study into another possible alternative market for waste glass. The University of Sheffield "ConGlassCrete" study concluded that waste container, plate, automotive and fluorescent tube glass could be used to make concrete. WRAP said the study had found "no significant" variation in performance between each type of glass, or even between clean and contaminated glass. Research was carried out in two phases. The first stage tested waste container glass for use as a replacement for pozzolana, an ash-like component of concrete. The second phase tested different kinds of waste glass in making concrete. The study found that the glass-concrete "complied with appropriate British Standards", and the results of the research have been backed by a pre-certification report from BRE.