Comparison Between Natural Weathering and Fluorescent UV Exposures: UVA-340 Lamp Test Results
SourceSamples of different polymers were exposed in Florida, Arizona and Ohio for two years. The same samples were exposed in a laboratory weathering chamber using two irradiance levels and two moisture cycles. The artificial and naturally weathered samples were then compared. With the exception of mildew growth, the laboratory exposures with moisture degraded the materials in a similar manner as seen outdoors. for a significant number of the samples, the lab exposures which included a condensation cycle gave better correlation than the cycles that were UV light only. For 9 of the 15 materials tested, the rate of degradation in the artificial weathering chamber was increased by increasing the light intensity level. In addition, the study confirms that acceleration factors are highly material dependent.