[en] Several severe radiological emergencies were reviewed to determine the likely range of conditions which must be coped with by a mobile teleoperator designed for emergencies. The events reviewed included accidents at TMI (1978), SL-1 (1961), Y-12 (1958), Bethesda (1982), Chalk River (1952 and 1958), Lucens (1969). The important conditions were: radiation fields over 10,000 R/h, severe contamination, possible critical excursion, possible inert atmosphere, temperatures from 50⁰C to -20⁰C, 100% relative humidity, 60-cm-high obstacles, stairs, airlocks, darkness, and lack of electric power