A report produced under the guidance of the Centre for Window & Cladding Technology's (CWCT) Technical Committee. It was based on the best knowledge available at the time of the publication. The guide was prepared because the volume of toughened glass currently in buildings has made nickel sulfide-induced failure of glass the subject of widespread discussion and it recognised that there was a lack of up-to-date information in the public domain. The contributing sub-group comprised members of the CWCT with relevant experience in the processing, specification and use of architectural glass. The guide aims to present information and considered opinion from a cross section of the industry . Some of the information is statistical, and its use in practice will require qualified engineering judgement. You can order a copy from: cwct@bath.ac.uk