Abstract: A switch operated to an open circuit condition by a closed lid of an automatic clothes washing machine. The switch housing is comprised of two parts which mate with each other and with the specially configured switch operating shaft for inhibiting entry of liquids into the switch contact chamber of the housing by splashing or by capillarity. A vent tube leads from the housing and, in effect, accepts air resulting from the air in the housing expanding when the switch is warm and which allows back flow of that air into the housing when the air in the housing cools. The tube prohibits pressure developing in the housing which is negative with respect to ambient atmospheric pressure.