[en] The electron transport parameters for both SF₆ and O₂ have been experimentally determined using the voltage transient method. The electron convective drift velocity (centre-of-mass velocity) W_e, the longitudinal diffusion coefficient ND_L, and the effective ionization coefficient α'/N were determined for electron swarm energies in SF₆ and O₂. For SF₆, the electron transport parameters were determined within the range 360 Td< E/N<720 Td and at a gas pressure range of p≅2 Torr. For O₂, the electron transport parameters were determined within the range 20 Td< E/N<270 Td and at a gas pressure range of 2< p<50 Torr. Here, E is the applied electric field and N is the gas number density