The present invention relates to a loose tube optical waveguide fiber
cable that is suitable for riser or plenum applications. The cable
includes a protective tube that loosely surrounds two or more optical
waveguides inside the hollow cavity defined by the tube. The protective
tube has an inner surface and an outer surface and is a dry structure.
Accordingly, the protective tube does not contain any gel-like compounds
or other materials around the optical fibers positioned inside the
protective tube. Strengthening members are disposed between the inner
surface of the protective tube and the outer surface of the protective
tube. The strengthening members are configured as embedded or layered
strengthening elements and are disposed longitudinally along the length
of the cable.