Investigating the role of educational centers as a constant source of noise pollution in urban areas - A case study of schools in Tehran metropolitan City

Undoubtedly, one of the main sources of noise pollution in cities is educational centers. The subject of discussion in the related studies has always been the effects of noise pollution on educational centers, but almost none of them have ever looked at the subject from the perspective that these centers can also be an important source of noise pollution in urban areas. Therefore, this research, with a different approach, addresses the effect of educational centers as an important source of noise pollution in urban areas. For this purpose, a total number of 32 state and nonprofit schools were selected randomly from the north, south, east, and west of Tehran City. After identifying the different sources of noise in the schools, the sound level was measured by TES sound level meter (model, 1358), at distances of 10, 20, and 30 m from the educational centers. The measured parameters included 10-minute equivalent sound pressure level (Leq10min), maximum sound level (Lmax), and minimum sound level (Lmin). Daily average sound level (Ld) was another parameter calculated for a period of 15 hours (from 7 am to 22 pm). According to the results, at the nearest distance to the schools (10 m), the highest average Lmax was 69 dB(A), measured at the time of students’ departure and its lowest was 64.7 dB(A) measured at the time the students had the physical education class. The highest and average Ld levels at the distance of 10 m from the schools were 65.2 dB(A) and 59.2 dB(A), respectively rep-orted from the male state primary-schools and female nonprofit high-schools. The average outdoor Leq and Ld level in the areas surrounding the target schools was about 5.5 dB(A) higher than the ambient noise. According to the results of the study, noise emitted from schools may be considered as a disruptive factor in urban environments, which needs to be addressed more.