Planning and Preparation It is recommended that an outside plant engineer conduct a survey of the cable route. Manholes and ducts should be inspected to determine the optimum splice point locations and duct assignments. Identify potential problems with innerduct and. Corning Optical Communications cable specification sheets are available which list the maximum tensile load for various cable types. The maximum pulling tension for stranded loose tube cable and ribbon cable is 600 lbF (2,700 Newtons). During installation, all curvatures should be smooth. Turn-backs and all sharp changes of direction. Duct Planning and Design Guidelines : Everyday questions are asked, what is the process of duct laying for optical fiber network, what will be duct planning and design procedure, what are the main things to be taken care of in duct laying.