Enclosure 1 constructed of panels 20 which can be joined by tongue and groove or press fit spline 46 and groove 26 technique. Acoustic shielding is achieved by properly selected materials of construction, e.g. syntactic, cellular composites. The doorway 10 of the enclosure is closed by a door 210 penetrated only by a guide 175. The latch mechanism 170 and 340 seals the door against the door jamb 185 by means of cam rollers 316 which engage indentations 189 (which may have specialized cam surfaces or inclined surfaces) along the door frame. The latch mechanism can be actuated from either side of the door by mechanical means engaging the guide.