Keep the paths clear
OSHA 1926.25(a) calls out work areas, passageways, and stairs by name — debris and scrap lumber get kept cleared from all of them. The storage standard adds the movement rule: 1926.250(a)(3) says aisles and passageways shall be kept clear to provide for the free and safe movement of material-handling equipment or employees, and kept in good repair.
That means a walkway isn't a place to set a toolbox 'for a minute,' stage material, or coil a hose. If a forklift or a loaded cart has to use the aisle, leave the clearance for it.