Applies to stevedoring operations performed by hand or hand trucks. Includes the incidental use of power driven escalators, conveyors or forklifts. Contemplates loading or unloading, stowing, shifting or trimming of cargo, transfer of cargo, supplies and material between vessels , transfer between string piece and point of deposit on dock and adjacent warehouses including tiering, sorting and breaking down, and operation of all mechanical equipment in connection with the above. Additionally contemplates the loading or unloading of grain, cement or other bulk pulverized materials or liquefied products when done by blower or suction tubes or pipe and hose conveyor systems. Includes employees engaged in the storage, maintenance or repair of nets, slings, forklift trucks or other equipment utilized by stevedoring concerns.