Abstract: A vacuum operated lithographic apparatus is disclosed. The apparatus includes a vacuum housing for providing a vacuum environment to a support constructed to support a patterning device, or a substrate table, or a projection system, or any combination thereof. An interior of the vacuum housing includes a plurality of transport circuits for transporting fluids and/or electrical signals for use in a first process mode for lithographic processing. At least one of the transport circuits is adapted to transport energy towards the interior of the vacuum housing to stimulate outgassing in the vacuum housing for use in a second process mode for bringing the lithographic apparatus into a vacuum operating condition.