26 LLE Review, Volume 77 Deciding when to replace spot-damage-afflicted fused-silica optics or, in the case of inaccessible, space-based lasers, predicting the useful service life of fused-silica optics before catastrophic, pulsed-laser-driven crack growth shatters a part has recently become simpler. By empirically deriving a rule for laser-driven crack growth in fused silica as a function of t...