The invention relates to a circuit interrupter including an insulating housing and, disposed therein, several pole units each comprising a pair of cooperable contacts and a pair of terminals electrically interconnected through the contacts.

At least the line terminals of the interrupter have disposed therebetween insulating barriers (49) which extend from the circuit interrupter housing a distance sufficient to prevent ionized gases at the terminals from intermixing before they have become sufficiently deionized to prevent conduction. This enables the circuit interrupter to operate at higher voltage levels.