The growth and recovery of the radiation-induced attenuation at 0.85 and 1.3µm have been measured in single-mode fibers. Moderate doses (~10 Gy) induce losses that are at least an order of magnitude greater than intrinsic, but the recovery observed in fibers not doped with P in the core or cladding is sufficient to eliminate the damage in a period of 1–24 h at 23°C.
E. J. Friebele, K. J. Long, and M. E. Gingerich, "Radiation damage in single-mode optical-fiber waveguides," Appl. Opt. 22, 1754-1757 (1983)