Assessment of solar ultraviolet radiation in Tabriz city, Iran

Background: the solar radiation consists of a vast spectrum of wavelengths such as visible light and ultraviolet radiation (uvr). the amount of uvr that reaches the earth's surface is very important due to its role in vitamin d synthesis and causing skin cancers. the hourly and daily mean values of solar uv type a, b, and visible light radiation were measured for the first time during the year. materials and methods: the hourly and daily mean values of uvr and visible light intensity of solar radiation at tabriz were measured and analyzed between the 2017 and 2018 years. the intensity of solar uva and uvb radiation was measured by hand-held lux-uv meter device from sunrise to sunset for one hour. results: the results showed that the highest values of uva and uvb radiation, reaching the earth were between 12 and 13 o’clock. the maximum and minimum values of uvr were recorded during the months of may and january, respectively. the maximum amounts of uva and uvb during the whole year were 52.48 and 2.82 w/m2, respectively. also, the lowest intensity of uva and uvb radiation during the whole year was 22.19 and 0.79 w/m2, respectively. conclusion: comparison of maximum and minimum uv amounts of type a and b in may was about 2.36 and 3.56 times more than in january. the measurements showed that the intensity of uva was significantly higher than uvb amounts.