Percival, S., Gray, N.F., Chalmers, R., and Sellwood, J. (2012) Microbiology of Waterborne Diseases. Academic Press, London (In Press)
Gray, N.F. (2010) Water Technology: an introduction for environmental scientists and engineers . (Third Edition) Elseiver, Oxford. 747pp. (Paperback and Hardback).
Gray, N.F. (2008) Drinking Water Quality: Problems and Solutions. (Second Edition) Cambridge University Press, Cambridge. 520pp. (Paperback and Hardback)
Gray, N.F. (2005) Water Technology: an introduction for environmental scientists and engineers . (Second Edition) Elseiver, Oxford. 610 pp. (Paperback and Hardback). Also co-published in North America by John Wiley and Sons Inc., New York.
Gray, N.F. (2004). Biology of Wastewater treatment. (Second Edition) Imperial College Press, London. 1440 pp. (Paperback and Hardback). Also co-published in Asia and North America by World Scientific Press, Singapore.
Gleeson, C and Gray, N.F. (2002) The coliform index and waterborne disease: problems of microbial drinking water assessment. Taylor and Francis Ltd., London. 210 pp. (eBook).
Gray, N.F. (2002) Water technology: an introduction for environmental scientists and engineers (Revised edition). Butterworth-Heinemann, Oxford. 548 pp. (Paperback).
Gleeson, C and Gray, N.F. (1997) The coliform index and waterborne disease: problems of microbial drinking water assessment. E. & F.N. Spon Ltd., London. 210 pp. (Hardback).
Gray, N.F. (1999) Water technology: an introduction for environmental scientists and engineers. Arnold, London. 548 pp. (Paperback). Also co-published in North America by John Wiley and Sons Inc., New York.
Gray, N.F. (1996) Calidad del agua potable: problemas y soluciones. Editorial Acribia, Zaragoza, Espana. 365 pp. (Paperback)
Gray, N.F. (1994) Drinking water quality: problems and solutions. John Wiley and Sons, Chichester. 315 pp. (Paperback and Hardback)
Gray, N.F. (1990) Activated sludge: theory and practice. Oxford University Press, Oxford and New York. 275pp. (Hardback).
Gray, N.F. (1989). Biology of Waste-water Treatment. Oxford University Press, Oxford and New York. 829 pp. (Hardback). (1992) (Revised Edition) Oxford University Press, Oxford and New York. 830 pp. (Paperback).
Gray N.F. (1988). Sugar beet processing in Ireland: a case study. Water Technology Press, Dublin. 412 pp. (Paperback).
Most recent refereed papers and book chapters
Hughes, T.A., Gray, N.F. and Guillamon, S. Removal of metals from acid mine drainage using liquid and dried digested sewage sludge and cattle slurry. Mine Water and Environment (in press)
Fryer, M. and Gray, N.F. (2012) Foaming Scum Index (FSI) – A new tool for the assessment and characterization of biological mediated activated sludge foams. Journal of Environmental Management , 110, 8-19.
Hughes, T.A. and Gray, N.F. (2012) Acute and Chronic Toxicity of Acid Mine Drainage to the Activated Sludge Process. Mine Water and Environment, 31, 40–52.
Fryer, M., O’Flaherty, E. and Gray, N.F. (2011) Evaluating the Measurement of Activated Sludge Foam Potential. Water, 3(1), 424-444.
Dubber, D. and Gray, N.F. (2011) The influence of fundamental design parameters on ciliates community structure in Irish activated sludge system, European Journal of Protistology, 47, 274-286.
Dubber, D. and Gray, N.F. (2011) The effect of anoxia and anaerobia on ciliate community in biological nutrient removal systems using laboratory-scale sequencing batch reactors (SBRs). Water Research, 45, (6), 2213-2226.
Dubber, D. and Gray, N.F. (2010) Replacement of chemical oxygen demand (COD) with total organic carbon (TOC) for monitoring wastewater treatment performance to minimize disposal of toxic analytical waste. J. Environ. Sci. Health, Part A. 45, (12), 1595-1600.
Brady, J. and Gray, N.F. (2010) Group water schemes in Ireland: Their role within the Irish water sector. European Water, 29, 39-58.
Gray, N.F. and Delaney, E. (2010) Measuring community response of benthic macroinvertebrates in an erosional river impacted by acid mine drainage by use of a simple model. Ecological Indicators, 10, 668-675.
Hughes, T.A. and Gray, N.F. (2010) Effectiveness and sustainability of active and passive systems for the treatment of acid mine drainage and the recovery of metals: A review. In: B.C. Robinson (ed), Mine Drainage and Related Problems, New York, Nova Scientific, pp.1-60.
Gray, N.F. (2009) Using charcoal to fix the price o carbon emissions. Sustainability: Science, Practice, and Policy, 5, (2), 1-3.
Dubber, D and Gray, N.F. (2009) Enumeration of protozoan ciliates in activated sludge: Determination of replicate number using probability. Water Research, 43, (14), 3443- 3452.
Hackett, M. and Gray, N.F. (2009) Carbon dioxide emission savings potential of household water use reduction in the UK. Journal of Sustainable Development, 2, (1), 36-43.
Kenny, T and Gray, N.F. (2009) A preliminary survey of household and personal carbon dioxide emissions in Ireland. Environment International, 35, (2), 259-272.
Kenny, T. and Gray, N.F. (2009) Comparative performance of six carbon footprint models for use in Ireland. Environmental Impact Assessment Review, 29, (1), 1 -6.
Gray, N.F. and Delaney, E. (2008) Comparison of benthic macroinvertebrate indices for the assessment of the impact of acid mine drainage on an Irish river below an abandoned Cu-S mine. Environmental Pollution, 151, (1), 31-40.
Guest editor
Gray, N.F. (ed.) 2012 Drinking Water and Health. Published as a special edition of the International Journal of Environmental Research and Public Health, 7-8, (2012)
Gray, N.F. (ed.) 2010 Drinking Water and Health. Published as a special edition of the International Journal of Environmental Research and Public Health, 7-8, (2010), 1597-4202; 97-469.
Gray, N.F. (ed.) (2006) Current Environmental Research in Ireland. Published as a special edition of the Journal of Environmental Science and Health: Part A. Toxic/Hazardous Substances and Environmental Engineering, 41, (5), 749-953.
Other publications
Gray, N.F. (2010) Failure of plastic media biofilters due to ponding caused by the fungus Subbaromyces splendens Hesseltine. Water Today, 1, (5), 86-90.