Given the importance that concentrating solar power technologies have had in recent years, the interaction between humid atmospheres in which SO2 is the main pollutant and the metal reflecting layers of the solar concentrators is a major concern that should be addressed. Previous durability studies have urged the importance of designing an accelerated aging test protocol for simulating aggressive industrial atmospheres that solar reflector materials are bound to encounter. Therefore, three types of reflectors were tested in an acid-rain (or Kesternich) chamber at various temperatures and gas concentrations based on the DIN 50018 and ISO 6988 standards. The results showed the significant effect of high SO2 concentrations rather than high temperatures on silvered-glass reflectors, although synergy should not be disregarded. Strong reductions in specular reflectance were found for one type of silvered reflector compared to another type, highlighting the significance of material processing and its effects on their final performance. Aluminum reflectors were not damaged as much as silvered-glass reflectors, but under microscopic inspection, a wide range of noticeable corrosion defects could be found in all the materials. Comparisons between the most representative Kesternich test and samples from an outdoor industrial site permitted realistic lifetime correlations for commercial silvered-glass reflectors. Main corrosion features that appeared in the reflective area of Type 1 silvered-glass reflectors at the end of the different corrosion tests. K_0_25 is the test at 0 dm3 SO2, 25 °C, K_0_40 is the test at 0 dm3 SO2, 40 °C, K_0_50 is the test at 0 dm3 SO2, 50 °C, K_0.2_40 is the test at 0.2 dm3 SO2, 40 °C, K_1_25 is the test at 1 dm3 SO2, 25 °C, K_1_40 is the test at 1 dm3 SO2, 40 °C, K_1_50 is the test at 1 dm3 SO2, 50 °C, K_2_40 is the test at 2 dm3 SO2, 40 °C, N is the sum of the number of corrosion spots visible to the naked eye at the end of testing on a 300 cm2 total reflector surface, Max. Pen. is the maximum penetration of corrosion near the edge (μm), Δρλ,φ is the mean increment in monochromatic specular reflectance on reflector surfaces not predamaged (-), Total Corr. is the mean total corrosion of the whole reflector surface (%). Display omitted •Suggested Kesternich tests for reflectors are 1 dm3 SO2 at 50 °C, 2 dm3 SO2 at 40 °C.•2 dm3 SO2 at 40 °C test implies an acceleration factor of 57 compared to a real site.•Major degradation appeared in Type 1 reflectors after the most aggressive tests.•Undamaged Type 2 reflectors had more and larger corrosion spots than Type 1.•Aluminum reflectors were corroded in a lower degree than silvered-glass reflectors.