1926.555 (a) (5) Where a conveyor passes over work areas, aisles, or thoroughfares, suitable guards shall be provided to protect employees required to work below the conveyors. 1926.555 (a) (6) All crossovers, aisles, and passageways shall be conspicuously marked by suitable signs, as required by subpart G of this part. 1926.555 (a) (7)Web