Building and Environment 40 (2005) 1255–1260 Determination of safe distance between roadway and school buildings to get acceptable school outdoor noise level by using noise barriers Yasar Avsar à , M. Talha Gonullu Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul, Turkey Received 15 April 2003; accepted 25 October 2004 Abstract Noise nuisance caused by road or highway depends on three main reasons; (1) type, speed and number of vehicles, (2) road surface structure sort and (3) characteristics of buildings and number of inhabitants. School buildings are often subjected to higher outdoor noise levels. Hence intelligibility of lessons by students is decreased. This study deals with relations between vehicle speeds and noise levels. Following the road study, without using any noise propagation processes, convenient school building–roadway distances were searched according to possible roadway traffic loads, number of lines and vehicle speeds. In this course, school building–road distance, barrier types and their arrangements, road surface types and vehicle speed limitations were offered. r 2004 Elsevier Ltd. All rights reserved. 1. Introduction Noise caused by traffic is the nuisance that is most often cited by roadside residents. School administrations and students living in the proximity of roadways will increasingly perceive noise problems. The effect of environmental noise on growing children has become one of the most important problems, because the personality, mentality and physique of children are being formed particularly at this early age. According to the some of the studies, students’ performance and behaviors can be changed both in high noisy ambience and quiet ambience [1]. The higher outdoor noise causes the higher indoor noise in classrooms. Disturbance from the outdoor noise is increased in hot seasons in the classrooms, especially when the windowpanes are open. Avsar et al. [2] dwelt upon an example from many educational buildings in this situation in Turkey. Furthermore, Avsar and Gonullu [3] put forward by measurements, that all educational buildings (54 primary and secondary schools and 16 high schools) in Fatih District of Istanbul had an outdoor noise level higher than 55dBA (as L Aeq ). Kurra [4] also investigated the effects of traffic noise on teachers’ annoyance in three high schools located in some busy areas of Istanbul. In that search, it was found that the correlation coefficient from traffic dose/response was as high as 0.876. In most countries, noise regulations suggest that the maximum outdoor noise level for educational buildings should be 55dBA (L Aeq ). This means that over 55dBA (L Aeq ) outdoor noise level at the facade of educational buildings will cause a decrease in educa- tional efficiency. By putting forward the adverse effects of higher outdoor noise levels on educational efficiency in schools, which has been stated by earlier studies, this study aimed to develop a discussion medium for a possible distance standardization between school and roadway in case of different types of noise barriers and other noise abatement materials between the noise source (traffic) and receiver (school). ARTICLE IN PRESS www.elsevier.com/locate/buildenv 0360-1323/$-see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.buildenv.2004.10.020 à Corresponding author. Tel.: +902122597070 (2838); fax: +902122619041. E-mail address: avsar@yildiz.edu.tr (Y. Avsar).