of the research results presented in the paper, Ultra High Volume Fly ash Concrete (UHVFA) concrete is urgently developed for widespread use in India using local fly ash. Urgent steps are also required to promote alkali activated pozzolan or geopolymer cement based concretes. In the geologic record Due to the ignition of coal deposits by the Siberian Traps during the Permian–Triassic extinction event around 252 million years ago, large amounts of char very similar to modern fly ash were released into the oceans, which is preserved in the geologic record in marine deposits located in the Canadian High Arctic. It has been hypothesised that the fly ash could have resulted in toxic environmental conditions. See also Alkali–silica reaction (ASR) Alkali–aggregate reaction Cement Coal waste Energetically modified cement (EMC) Health effects of coal ash Pozzolanic reaction Silica fume Cenocell References External links Evaluation of Dust Exposures at Lehigh Portland Cement Company, Union Bridge, MD, a NIOSH Report, HETA 2000-0309-2857 Determination of Airborne Crystalline Silica Treatise by NIOSH American Coal Ash Association Fly Ash Info, the Ash Library Website, University of Kentucky United States Geological Survey – Radioactive Elements in Coal and Fly Ash (document) Public Employees for Environmental Responsibility: Coal Combustion Waste UK Quality Ash Association : A site promoting the many uses of fly ash in the UK Coal Ash Is More Radioactive than Nuclear Waste, Scientific American (13 December 2007) UK Quality Ash Association A web site providing further information on the applications for PFA. Asian Coal Ash Association A web site providing further information on technologies and trade related to coal combustion products. Cement Coal Coal-fired power stations Concrete Environmental impact of the coal industry Environmental impact of the energy industry Silicates Waste Waste treatment technology Types of ash By-products