1. Introduction:
It is generally admitted that external noise in the community is legally classified as "noise pollution" and its effects on human health are well documented in Europe and America. To date, from empirical observations, there is growing evidence that due to the global changes in human behaviour even in African towns, peoples tend to be 24 hours a day, 7 days a week hyperactive, and this has significantly impacted urban environmental noise, and consequently social activities. One of documented effects noise pollution are the negative impact on vigilance and impairment of cognitive functioning, particularly performance school children.
Objective :
Reporting the level (dB) of ambient noise around primary/secondary schools in urban area in Yaoundé, Cameroon, and discussing the known impact.
Methods
This study included 34 primary/secondary schools in Yaoundé, Cameroon. Noise level measurements : Data were collected using a digital sound meter (SonoMeter Software) calibrated and adjusted to the human ear’s sensitivity. We operated in a sampling distance of 5m near classrooms walls, outside. Tests were performed on Tuesdays and Fridays between 8:30 and 11:30, period when the cognitive performance during learning is most critical according educational scientists. Measurements under the influence of atypical sources were cancelled.
Noise level was operationally defined as higher (>65 dB) and lower exposure (<65 dB).
Results
All sites exceeded the higher level exposure (>65 dB) as stated by WHO concerning comfortable environmental noise levels (34/34 schools). No significant noise level differences were identified regarding the fact that it is public or private school; however, higher thresholds were found in public schools when comparing number of noise sources (road. Commercial activities, etc…). Surprisingly, early morning (8.30) measurements showed a lower levels of noise than late morning.
Conclusion
The acoustic environment observed in this propedeutic study, near educational institutions are of fundamental importance in that there is a negative impact of adverse listening conditions on speech understanding in class. We postulate that noisy environment as defined by WHO is a barrier of learning and then a barrier of development of our country.
This is pilot phase, next will be children’s performance on standardized tests for arithmetic, reading, writing, and memory performance tests. this in order to provide decision maker with "noise map" and its negative social impact.