Light and filter support structure

Claim 1

A clean room ceiling structure for providing an uncontaminated downward flow of air comprising: a plurality of rigid, elongated rail members interconnected in an orthogonal grid to define a matrix of adjacent rectangular spaces, at least some of the rail members including: an elongated body, a medial wall protruding vertically therefrom, a pair of opposed side walls protruding vertically from the body on opposite sides of the medial wall, each side wall defining with the medial wall an upwardly-open channel therebetween for receiving a gel-like sealant, the side walls and medial wall including ridges for retaining the sealant, a pair of opposed lower side walls depending downwardly from the body to define a channel therebetween; a light-transmissive closure strip attachable to the lower side wall to define therewith an enclosed, generally rectangular tube for receiving entirely therein a fluorescent light fixture, the closure strip being removed to permit access for relamping and service, the closure strip further having a lower surface defining a lower plane; a light fixture attached to the rail and received between the lower walls such the light fixture may be fully enclosed within the tube by the closure strip; and a plurality of rectangular filter panels occupying substantially all the grid spaces such that air may flow through all the spaces without substantial turbulence as would occur if one or more of the spaces were blocked against airflow, the filter panels having peripheral downwardly-depending flanges received up the upwardly-open channels of the rails to seal the ceiling whereby air flow between a space above the ceiling and a space below the ceiling must pass through the filter panels, each filter panel further having a lower filter surface occupying the lower plane such that the ceiling has a generally flush undersurface permitting close unobstructed attachment of divider walls below the ceiling, and minimizing the airflow obstruction by said light fixtures.