Frederick A. Steart, draughtsman, surveyor and mine manager, was the eldest son of William Steart, mining engineer at Bath, England. He was educated at Bath and worked as a colliery surveyor in Somersetshire. He became a certified mine manager, was elected a Fellow of the Geological Society of London, and was a member of the Institute of Mining Engineers. He was a Freemason, and in 1906 married Edith Bremner.
Steart came to the Transvaal Colony in June 1903 to join the Geological Survey in Pretoria as a draughtsman. From November 1904 to January 1905, with H. Kynaston* and A.L. Hall*, he surveyed and mapped the geology of Pretoria and environs on a scale of 2 inches to the mile (1:31 680). With Kynaston, E.T. Mellor* and Hall he produced another geological map of Pretoria, on a scale of 1000 Cape roods to the inch (1:148 752), which was published in 1907. He was furthermore the co-author, with A.L. Hall, of a paper "On faulting and folding in the Pretoria Series and the dolomite", published in the Transactions of the Geological Society of South Africa (1905, Vol. 8, pp. 1-6).
In July 1908 Steart was appointed deputy commissioner of mines for Natal and inspector of mines for the North-West District, stationed in Dundee. In October 1910, after the creation of the Union of South Africa, he became assistant inspector of mines in the province of Natal. His publications included "Some notes on the geology of the north-west portion of the Natal coalfield" (Transactions of the Geological Society of South Africa, 1919); "Coal in Natal" (Colliery Guardian, 1930); "History of Natal coal mining" (South African Mining Yearbook, 1932); and, at the age of 79, "Mining subsidence with particular reference to the coalfields of South Africa" (Coal and Base Minerals of South Africa, 1956). His experiments in connection with mine ventilation showed that six suitable aeroplane propellors, mounted in tandem on the same shaft, could provide some 140 cubic meters of air per second and in 1921 he patented this propellor fan. It altered the whole conception of mine ventilation by means of fans and was a forerunner of the axial flow fan, which came to be used in many mines.
By 1906 Steart was a member of the Geological Society of South Africa and of the South African Association for the Advancement of Science, though his membership of the latter had lapsed by 1910. After the death of his first wife in 1936 he married Ellen I.S. Palmer, who survived him.