Impact of Road Traffic and Other Sources of Noise on the School Environment

The scale of traffic noise problems and its impact on the indoor environment of schools were investigated in 105 of 351 schools in Singapore. The assess ment of traffic noise was made objectively, and its impact on the background noise levels in schools was evaluated, using speech intelligibility tests and a subjective survey. The results showed a significant reduction in speech intelli gibility when the background noise was raised from 55 to 65 dBA. Methods of effecting noise control in class-rooms have been investigated, from which it was shown that noise reduction of up to 6 dBA can be achieved without major changes to the architectural design and cost. Thus road traffic noise has a significant impact on the acoustical performance of schools in cities with a high population density, especially those situated in hot and humid climatic zones, where natural ventilation is essential for thermal comfort.