Fehrm was born in Järna, Vansbro Municipality, Sweden, the son of Fritz Fehrm, a bookseller, and his wife Klara. He passed studentexamen in Falun and initiated studies at the KTH Royal Institute of Technology in Stockholm, from which he graduated with a degree in electrical engineering in 1932. With a keen interest in radio technology, he received the following year employment at the Royal Swedish Army Materiel Administration. In 1940, Fehrm came as a 3rd degree flight engineer to the Royal Swedish Air Force Materiel Administration, where he would stay until the war was over. During the war years he developed into an expert on eco-radio and participated actively in the special working group that had been created for the area within the Swedish Board of Inventions. His expertise was also used for the investigation of advanced military equipment, which ended in the country crashed airplane or in any other way, for example the Bäckebo rocket. Fehrm became 2nd degree flight engineer in 1942. Fehrm was head of department at the Swedish National Defence Research Institute from 1945 to 1957 when he was appointed Director General of FOA. Fehrm held this post until 1968. He was then Director General of the National Swedish Board for Technical Development from 1968 to 1971. He became a member of the National Board of the Swedish Institutes of Technology in 1959. Fehrm was chairman of the Swedish Natural Science Research Council from 1965 to 1977, and the Stamnätsnämnden from 1966 to 1985. He was a member of the Swedish Government Research Advisory Board from 1962 to 1978, the Miljövårdsberedningen from 1968 to 1977, and the Swedish Transport Research Delegation from 1971 to 1982. Furthermore, Fehrm was chairman of the board of the AB Atomenergi from 1969 to 1976, chairman of the Swedish Association of Graduate Engineers from 1972 to 1973, and 1st vice chairman of the Swedish Association of Graduate Engineers from 1974 to 1977.
Personal life
He was married to Ragna Fägersten, the daughter of Helge Fägersten and Signe Janzon.
