The UV lamp aging test uses fluorescent UV lamps to simulate the destructive effects of sunlight on durable materials. This is different from the aforementioned xenon arc lamp. The fluorescent ultraviolet lamp is similar in electrical principle to ordinary cold-light fluorescent lamps for lighting, but can generate more ultraviolet light instead of visible light or infrared light.
For different exposure applications, there are different types of lamps with different spectra to choose from. The lamp can simulate sunlight well in the main short-wavelength ultraviolet spectral range. The spectral energy distribution (SPD) of the UVA lamp is very similar to the spectrum obtained at 360nm in the solar spectrum. UVB lamps are also commonly used lamps for accelerated artificial weathering tests. It destroys materials faster than UVA lamps, but its energy output with a wavelength shorter than 360 nm will cause deviations from actual test results for many materials.
Although the national standard stipulates and the currently prevailing domestic aging test method is xenon arc radiation, xenon arc radiation and ultraviolet light aging tests are both widely used test methods abroad. These two methods are based on completely different principles. The xenon lamp irradiates the test chamber to imitate the entire solar spectrum, including ultraviolet light, visible light and infrared light, and its purpose is to simulate sunlight. The ultraviolet aging test does not attempt to imitate the sun's rays, but only imitates the destructive effect of the sun's rays. It is based on the principle that durable materials that are exposed outdoors for a long time will have greater aging damage caused by shortwave ultraviolet light.