Abstract

Todays, Climate change can be effect on the intensity of ultraviolet (UV) radiation and cause of many human diseases. In this cross-sectional study, changes of the intensity of UV ray were associated with the changes in latitude and longitude, height, climatic conditions, natural and human-made artifacts. Given that the highest radiation intensity was at the beginning of the summer, the radiation rate of UV ray in Mashhad was measured in the summer using a Hagner radiometer, the UV-A model. The radiation rate of the UV ray was determined in 2000 stations, which were 5km far from each other. Data were analyzed using SPSSv16 software, T-test, and ANOVA tests. The results of this study showed that the radiation rate of UV ray in Mashhad was 0.49+/-0.143mSv per year. The findings showed that latitudinal and longitudinal changes did not have a significant effect on the intensity of UV radiation (P > 0.001). The changes in the height above the sea level influenced the irradiance rate of UV and increasing the height above the sea level raised UV radiation (P < 0.001). Human artifacts significantly changed the rate of UV radiation (P < 0.001). Cloudy, semi-cloudy and sunny conditions had the most effects on UV radiation (P < 0.001). The results revealed that the average rate of UV ray in Mashhad was below the global standard (10W/m(2) for UV ray), and traffic in open air could not be risky.