Patent ID: 8156708

Claim:
A ceiling system for a room in which there is an explosion threat, and for containing fragments and for diffusing gases resulting from an explosion, the room having a ceiling support grid, comprising: a tiled arrangement of gravel modules supported by the ceiling support grid; wherein each gravel module comprises: a box frame, containing at least a bottom layer of screen gravel and a top layer of graded gravel; a first crisscross pattern of bridge cable across the bottom of the box frame; a screen gravel support stack above the first crisscross pattern of bridge cable, for supporting the screen gravel, the screen gravel support stack having a first set of layers of wire mesh, and at least one layer of closed material; a graded gravel support stack above the screen gravel, for supporting the graded gravel, and having a second set of layers of wire mesh; a third stack of wire mesh above the graded gravel; and a second crisscross pattern of bridge cable above the third set of layers of wire mesh and across the top of the box frame.