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A study evaluating noise levels at selected schools in the Czech Republic.

OBJECTIVE
Worldwide, primary schools are the most important segment of childhood education. The main disturbing source of noise in schools is human speech, the primary component of the learning process. School noise has a negative impact on information processing, teachers and pupils, and communication in the classroom. The study aimed at assessing A-weighted sound pressure levels in primary school classrooms. It was concerned with A-weighted sound pressure levels and their fluctuation during various classes.


METHODS
The noise was measured with the static calibrated Brüel and Kjær 2260 Investigator sound level meter. The sound pressure levels were measured twice in 12 classes as 11 different subjects were taught to reduce the uncertainty of results due to their potential variability in time. From the instantaneous values, LA (t), equivalent continuous A-weighted sound pressure levels (LAeq,T) and LAmax were calculated.


RESULTS
The mean equivalent A-weighted sound pressure level during lessons irrespective of age and subjects taught was 68.0 ± 3.4 dB (uncertainty of measurement). The highest levels of noise were in physical education and arts; the lowest levels were found for English taught as a foreign language. There were no statistically significant differences in LAeq,T depending on the numbers of children in the classes. The main source of noise is pupils. Attention should be paid to negative feelings of noise to reduce LAeq,T in schools.


CONCLUSIONS
Continuous noise pollution, in combination with stress and the mentally demanding nature of the teaching profession, may lead to numerous negative effects on human personality.