Fan filter mounting frame

A method of supporting an equipment unit with a suspension grid system, wherein the suspension grid system includes a number of rails and cross rails that define the sides of an array of generally rectangular cells having open interiors, the rails and cross rails comprising T-shaped members, the T-shaped members including generally vertical stems and generally horizontal support legs extending outwardly from lower portions of the stems, the support legs forming rail support flanges on the stems for supporting the equipment in the cell, the method comprising the steps of:

• cooperatively sizing the equipment unit and at least one cell so that the equipment unit may pass upwardly through the open interior of the cell without displacing or otherwise disrupting the suspension grid system;
• passing the equipment unit upwardly through the open interior of the cell to a position above the rail support flanges;
• displacing the equipment unit in a diagonal direction toward one corner of the cell, such that a corner of the equipment is positioned above the rail support flanges adjacent said one corner of the cell, with a diagonally opposite corner of the equipment unit being horizontally spaced from the rail support flanges adjacent thereto;
• providing frame inserts that fit on the rail support flanges adjacent said opposite corner and extend under the equipment unit so as to provide supporting engagement between the rail support frame flanges and the equipment unit along the sides adjacent to said opposite corner, and providing interlocking flanges for releasibly securing the frame inserts in a generally horizontal, equipment supporting position on the rail support flanges of the rails;
• placing the frame inserts on the rail support flanges on the sides of the cell adjacent said opposite corner;
• and
• lowering the equipment downwardly into supporting engagement in the cell, with the equipment resting on and being supported directly by the rail support flanges of the T-shaped members along two adjacent sides of the cell adjacent said one corner of the cell and with the equipment resting on and being supported by frame inserts at sides adjacent the opposite corner of the cell.