Circuit interrupters such as breakers with a metal arc chute having a base and sidewalls extending outward from the base forming an open cavity, a movable arm holding a movable contact adjacent to the arc chute, a line conductor electrically connected to a stationary contact residing adjacent to the arc chute facing the movable contact and a three-dimensional molded arc quenching insert attached to the metal arc chute, and residing in the cavity of the metal arc chute between the stationary and movable contacts. The insert has an arc quenching material that optionally releases a gas such as hydrogen during an arcing event.