evaluation of noise pollution and traffic noise index using geographical information system in the main streets of kashan, iran

background : studies have shown that noise pollution has harmful effects on human health. the sound of traffic is the main source of noise pollution in cities. the purpose of this study was to determine noise pollution using a geographical information system (gis) in the main streets of kashan, iran. methods: in this study, 180 noise samples were collected from 20 regions of the main streets in kashan using a cel-440 sound level meter with the iso 1996 procedure. in each measurement, equivalent sound level, statistical sound level, and the minimum and maximum noise levels were determined in 3 periods of morning (7-10:30), noon (12-15:30), and night (18-21:30) and the traffic noise index was calculated and displayed on gis maps. findings: the mean and standard deviation for the equivalent sound level in all measurements was equal to 77.2 ± 1.1 dba and the average of the traffic noise index was 68.5 dba. a significant difference was observed between the studied stations in terms of the traffic noise index (p < 0.001), but significant differences were not observed between these stations in terms of the equivalent sound level (p = 0.14). conclusion: noise pollution in kashan was higher than the iranian environmental protection organization standard. the main cause of noise pollution in this city is motor vehicles; thus, control procedures are necessary in this area.