Abstract: A cable can inhibit water that may inadvertently enter the cable from flowing lengthwise within the cable. The cable can include an outer jacket and at least one optical fiber disposed within the outer jacket. Water blocking barriers can be disposed at different longitudinal locations along the cable, and each water blocking barrier can provide a seal. Each barrier can include a polymer or a cured material and at least one derivative of at least one initiator that induces a reaction with the polymer or the cured material. The at least one initiator can include at least one of a photoinitiator or a thermal initiator.

Abstract: A fiber optic cable can inhibit water that may inadvertently enter the cable from flowing lengthwise within the cable. The fiber optic cable can include a buffer tube defining an interior volume extending along the cable. Water blocking barriers can be disposed in the buffer tube intermittently along the length of the cable. The barriers can be formed from a UV and thermal cured material and can comprise an acrylic. The barriers can be applied to the optical fibers or to a carrier tape that is wrapped around the optical fibers or fiber bundle. The barriers (or carrier tape) can be disposed against and/or adhere to an inner surface of the buffer tube to provide intermittent water blocking. Each barrier can provide a seal around the optical fibers and can limit flow of water in the interior volume.

Abstract: A fiber optic cable can inhibit water, that may inadvertently enter the cable, from damaging the cable's optical fibers. The fiber optic cable can comprise buffer tubes extending along the fiber optic cable. The buffer tubes can be arranged such that a ring of buffer tubes surrounds one or more centrally located buffer tubes. Stacked ribbons of optical fibers can be disposed in each buffer tube, along with water-swellable tape and water-swellable yarn. The tape, yarn, and optical fibers can be dry or free from water-blocking gels or fluids. The water-swellable materials can provide an unexpected level of water protection. The water-swellable materials can, for example, limit flow of seawater within the buffer tubes. In an exemplary embodiment, progression of seawater can be limited to three meters or less for a twenty-four hour test period during which the seawater is under about one meter of head pressure.

Abstract: A fiber optic cable can inhibit water, that may inadvertently enter the cable, from damaging the cable's optical fibers. The fiber optic cable can comprise a buffer tube defining an interior volume extending along the fiber optic cable. Optical fibers can be disposed in the interior volume of the buffer tube, along with water-swellable materials, such as tapes and yarns. The interior volume can be dry or free from water-blocking gels or fluids. The water-swellable materials can provide the fiber optic cable with an unexpected level of protection from seawater. The water-swellable materials can, for example, limit flow of seawater along the interior volume. In an exemplary embodiment, progression of seawater in the interior volume be limited to three meters or less for a twenty four hour test period during which the seawater is under about one meter of head pressure.

Abstract: A fiber optic cable can inhibit water, that may inadvertently enter the cable, from damaging the cable's optical fibers. The fiber optic cable can comprise a buffer tube defining an interior volume extending along the fiber optic cable. Optical fibers can be disposed in the interior volume of the buffer tube, along with water-swellable materials, such as tapes and yarns. The interior volume can be dry or free from water-blocking gels or fluids. The water-swellable materials can provide the fiber optic cable with an unexpected level of protection from seawater. The water-swellable materials can, for example, limit flow of seawater along the interior volume. In an exemplary embodiment, progression of seawater in the interior volume be limited to three meters or less for a twenty four hour test period during which the seawater is under about one meter of head pressure.

Abstract: A method and apparatus for determining and controlling the excess length of a communications element disposed in a conduit is disclosed. The method includes the steps of measuring the length of a communications element being disposed within the conduit, placing a mark on the conduit each time a pre-determined length of the communications element is disposed within the conduit, and measuring the distance between the marks on the conduit. The excess length is determined by comparing the distance between the initial mark and the subsequent mark on the conduit to the measured length of the communications element disposed within the conduit. To control the excess length ratio, the conduit may be stretched, or process parameters related to formation of the conduit may be changed.