A rotary switch housing (100), comprising a bottom wall (102) for mounting of the switch housing (100) to a mounting base, and side walls (104, 106) extending from the bottom wall (102), the switch housing further comprising an arc chamber (120) for extinguishing an electric arc, and a gas exhaust channel (130) for exhausting gas developed in the arc chamber (120) out of the housing (100). The gas exhaust channel (130) comprises a guiding portion (130A), which is substantially parallel to a side wall (106) of the housing (100) for leading the gases to a direction away from the bottom wall (102) of the housing (100).