Does flex-hose need to be grounded?

Short pieces of Flex Hose (5’ and under) do not have to be grounded. For longer Flex Hose lengths, you can use the internal wire in the Flex Hose as a grounding wire, if desired. To ensure conductivity, strip and bare the end of the internal wire so it contacts the metal duct to which the Flex Hose is attached. To minimize reductions in airflow and static pressure, Flex Hose should only be used for the final run between the Snap-Lock Ductwork and the woodworking tool.