Abstract: A raised access floor has panels suspended by pedestals. Each panel may have a top surface and a frame extending around the top surface. Each panel may have extruded aluminum components including four edge members, two intermediate members, and a center member. Each edge member may have a frame portion with a box beam configuration. The frame portions can be press-fitted with corner members to provide the frame. Two edge members, the intermediate members, and the center member may have top surface portions coupled together to form the top surface. The top surface may be supported by support ribs with enlarged bottom ends that resist bending. The ends of the support ribs are press-fitted against the frame. Components may be modified or removed to alter the panel geometry. A cover plate may be used to cover the top surface. The cover plate and/or top surface may be continuous or perforated.

Abstract: A sealable ceiling assembly is provided for use in applications such as clean rooms. The sealable ceiling assembly may include main beams suspended from a support ceiling parallel to each other and cross beams that run perpendicular to the main beams to attach the main beams together. Each cross beam has a bore from which coupling members extend to either side. Each coupling member has a head with a cam surface designed to interlock with a retention slot of the main beam in response to ninety-degree rotation of the coupling member. The coupling members are attached within the bores of the cross beams via set screws that can be rotated after engagement to urge retraction of the coupling members into the bore to tighten engagement of the cross beams with the main beams. Stiffeners may be attached to top nut slots of any of the beams that need reinforcement.