Abstract: To assess relative degradation resistance of different materials, one or more samples of each of the materials is irradiated with a beam of laser. The laser is chosen or tuned such that the laser beam has no wavelength sufficient to cause a photochemical reaction in material samples but the degree of irradiation is sufficient to degrade each material. A measure of degradation of each material sample is determined in consequence of the irradiation. The relative degradation resistance of each material is ranked based on these measures of degradation. In one approach, each sample may be irradiated until about the same pre-selected laser energy has been absorbed by the sample. In another approach, each sample may be irradiated for about the same time, while maintaining the irradiated portion of the sample at a same pre-selected temperature.