The response of the National Ignition Facility target chamber first wall to the x rays and debris ions emitted by the target is important to the conceptual design of the facility. The material that is vaporized by the target emanations can condense on the laser optics, rendering them too opaque for laser transmittion. This paper presents results of computer simulations of the vaporization of graphite and boron from the target chamber walls, using x-ray and debris ion spectra from target breakup simulations performed at the University of Wisconsin.