David Muir worked for Bristol City Council, mainly on air quality, from 1976 to 2009 and since taking early retirement has worked as an independent consultant and researcher. He is both a Chartered Environmentalist and Chartered Scientist and has regularly interviewed prospective CEnvs.

David gained his PhD in 2003 from the University of the West of England where one of his supervisors was Jim Longhurst. The subject was developing a means of identifying the sources of PM10 during pollution episodes and David has since given papers at international conferences and has had a number of papers published. He was a founder member of the Institute of Air Quality Management and served on the IES Council from 2006-16.