The biggest risk when adding new fibre to existing pole lines is actually during the installation process. When new cables are lashed to communications strand,

The biggest risk when adding new fibre to existing pole lines is actually during the installation process. When new cables are lashed to communications strand, the 45 pound cable lasher causes the strand to swing back and forth quite significantly, making the tops of nearby poles swing several feet or more. As a result, insulators that are old and of certain types that may develop cracks can break off during lashing. Direct or even indirect contact with a 7.2kV or 16.8kV primary by communications workers can be deadly, and is a real risk of this kind of work.