Abstract: A water blocking configuration for a low temperature, dry loose tube fiber optic cable includes one or more flexible buffer tubes each having a passage sized to contain one or more optical fibers. A single yarn is disposed in the passage of each buffer tube, and the yarn has a denier of not more than 1500. The yarn is coated with particles of a water absorbent material having a size distribution of between zero and not more than 160 microns. A dry loose tube fiber optic cable having the disclosed configuration meets the Telcordia GR 20 (Issue 2) industry standard with respect to water penetration, change of fiber attenuation, and fiber tensile strength at a low temperature of ?60 degrees C.

Abstract: A water blocking configuration for a low temperature, dry loose tube fiber optic cable includes one or more flexible buffer tubes each having a passage sized to contain one or more optical fibers. A single yarn is disposed in the passage of each buffer tube, and the yarn has a denier of not more than 1500. The yarn is coated with particles of a water absorbent material having a size distribution of between zero and not more than 160 microns. A dry loose tube fiber optic cable having the disclosed configuration meets the Telcordia GR 20 (Issue 2) industry standard with respect to water penetration, change of fiber attenuation, and fiber tensile strength at a low temperature of ?60 degrees C.