Born on 1 October 1911 the only son of Alexander Mair, seed merchant, and Margaret Middleton his wife, he was educated at Turriff High School, Aberdeenshire and qualified from Aberdeen University in 1934. After serving as house surgeon at the Royal Infirmary, Oldham, and resident surgical officer at St Martin's Hospital, Bath and the Royal Infirmary, Blackburn, he was senior surgical registrar at the Royal Northern Infirmary, Inverness. During the war of 1939-45 he served in the RAF volunteer reserve, with the rank of Flying Officer. Mair became interested in thoracic surgery, served as senior surgical registrar at the Liverpool Chest surgical centre, Broadgreen Hospital, and was then appointed thoracic surgeon to the thoracic surgical unit at Castle Hill Hospital, Cottingham, Yorkshire. He lived at Audsley, Swanland, North Ferriby, where he died on 5 June 1952 aged 40, survived by his wife Dr Marjorie Dainton, whom he had married in 1941. There were no children.