52 / | HD | STATIC STRUCTURES (E.G., BUILDINGS) |
272 | DF | INTERSECTION OF WALL TO FLOOR, CEILING, ROOF, OR ANOTHER WALL (I.E., TWO-WAY CORNER CONSTRUCTION) {8} |
284 | DF | .~ Block type or modular panel type {2} |
286 | .~.~ Block type having vertical and horizontal keys |