Evaluation of noise pollution and acoustic comfort in the classrooms of Hamadan University of medical sciences in 2012

Noise pollution cause mental fatigue، concentration disturbance and learning loss in students during the training activities. This study aims to evaluate Noise pollution and the level of acoustical comfort in typical classrooms، and present treatment methods for improving acoustic comfort. In cross sectional study، twenty classrooms in the seven faculty of Hamadan University of medical sciences، were studied using questionnaire with reliability coefficient equal to 0. 8 was completed among 413 students. Measurement of noise level was performed using sound level meter (model TES-1358) according ANSI S12. 6 in classrooms. The results showed the background noise level and outdoor noise level were equal 46. 97 ± 3 dB (A)، and 57. 16 ± 4. 8 dB (A)، respectively. The background noise was higher than the recommended limit equal to 45 dB (A) (P<0. 01). The construction activities are most important annoying factor and concentration disturbance are most complication of noise. Signal to noise ratio within the classroom was 13. 14±3. 54 dB (A)، which was inappropriate compared with the recommended limit 15 dB (A) (P<0. 01). The difference in speech intelligibility at various levels of signal to noise ratio was significant (p<0. 05). The results confirmed the studied classrooms haven’t acceptable acoustic conditions and background noise level was affected by outdoor noise. In regard to confirmation of the effects of noise on the student attention، the acoustic interventions is must be considered.