[2][3] He worked as a teacher at Lycée de Sens (Yonne), where he was granted an indefinite leave of absence after a year due to health issues.
During that period he was invited by Pierre Massé to join a statistics research group on hydrology at Societe hydro-technique de France (SHF).
[3][4] With the creation of Électricité de France in 1946, Étienne Halphen and his group including Lucien Le Cam and Georges Morlat were attached to the Service des Études et Recherches Hydrauliques.
[1] Posthumously: An overview of Halphen's work on probability distributions is given by Georges Morlat.
[22] Étienne Halphen received the Prix Montyon de Statistique of the Académie des sciences posthumuosly in November 1954 for his work on statistical hydrology.