Journal of North Khorasan

Abstract Background & Objectives: Sun is the most important natural source of UV light. Exposure to ultraviolet radiation causes harmful effects on the individual. This study aimed to measure the intensity of UV-A in Bojnurd in 2012-13. Method and Materials: In this cross - sectional study, the intensity of type A ultraviolet ray in Bojnurd was measured in one year by using a Hagner radiometer. Measurements were done in each month, at three time in the morning, afternoon and evening, five geographic directions, in two heights of hand and eye and three weather of sunny , partially cloudy and cloudy. Data were analyzed with SPSS16 software using T-Test and ANOVA test. Results: The results showed that the average intensity of UV rays in the summer is upper than the standard value (10 watts per square meter). The maximum intensity of UV-A was in August with a monthly average of 12w/m2 and the minimum monthly average was in February with 2 w/m2. The results showed significant difference between the intensity of UV rays in the seasons, months, times and different climatic conditions exist (P = 0.000) and difference between the intensity of UV rays in directions (P= 0.987) and different heights of body (P = 0.480) was not significant. Conclusions: According to the prevalence and increased incidence of skin cancer in Province in recent years, it is recommended that workers who work outdoors, especially in the summer sun as much as possible to reduce the stopping time and use of appropriate personal protective equipment.