Sisal, hemp or other baled fibers shall not be handled, loaded or unloaded at a terminal without permission. These materials shall, unless permission is secured, be unloaded to lighters; if such materials are unloaded onto a mooring facility with such permission, they shall be removed therefrom immediately after unloading unless the manager otherwise permits. Stacks shall not be higher than 12 feet, or when palletized, three pallets high, except by permission of the manager. The sides exposed to aisles or driveways shall be protected with tarpaulins when the manager shall so direct. Access to the areas where such material is stored shall be limited to the working personnel and watchmen only.