Noise Pollution and Traffic Noise Index on Mashhad Main Streets during the Busiest Hours of Summer

Authors

1 Assistant Professor, Medical Physics Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Professor, Medical Physics Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.

3 M. Sc. in in Medical Physics, Mashhad University of Medical Sciences, Mashhad, Iran.

Abstract

Introduction: Among the environmental pollutions, noise is very important for its physiological 
and psychological effects on human. Traffic noise is one of the most important pollutants and the 
hospitals  are  one  of  the  critical  places  regarding  this  type  of  noise.  For  these  reasons,  in  the 
summer  of  1382,  the  traffic  noise  of  Mashhad  main  streets  around  the  hospitals  was  assessed 
during the busiest hours. 
Materials and Methods: The noise indexes such as L Aeq , L Afmax , L 10 , L 50  and L 90  were measured 
by a Sound-Level-Meter, model Investigator 2260. The traffic load was also determined. On the 
basis  of  these  results,  Noise  Pollution  Level  (NPL)  and  Traffic  Noise  Index  (TNI)  were 
calculated. The assessment was done during three different periods of the days in twelve stations.  
Results: Based on the obtained results, the maximum L Aeq  was recorded on Bahar Street during 
the morning hours and on Koohsangi Street during the noon and night periods. Throughout the 
three  periods  the  maximum  NPL  and  TNI  were  estimated  on  Bahar  and  Nakhrisi  Streets, 
respectively.  The  correlation  between  all  of  the  indexes  was  analyzed  and  a  logarithmic 
correlation was observed between L Aeq  and the traffic load.  
Discussion  and  Conclusion:  On  the  basis  of  the  noise  standard  in  free  field  in  Iran,  noise 
pollution is a serious problem in Mashhad. 

Keywords

Main Subjects


Volume 2, Issue 3 - Serial Number 3
September and October 2005
Pages 21-30
  • Receive Date: 02 July 2005
  • Revise Date: 10 August 2005
  • Accept Date: 15 August 2005
  • First Publish Date: 01 September 2005