Quiet environment is essential for improving quality of living and rest. For example, noisy neighbors degrade quality of sleeping of residents. Due to emphasis on energy saving of buildings, more insulation and tighter sealing is applied for windows, doors, and walls of new buildings. As results, not only energy dissipation of new building is reduced, but also interior of new buildings have become significantly quieter. However, sound and heat insulation performance of existing buildings is relatively worse, when compared to that of recent buildings. As elapse of time, gap between bricks or concrete of building and sealing grows larger, worsening of sound and heat insulation performance of buildings is unavoidable. To provide quiet room for quality control of products or other purposes in noisy environment, indoor noise chamber is required in practice. In present work, sound transmission through indoor noise chamber is measured using different noise sources. For the worst case, noise source and sound transmission of door slam noise is shown.

• 조용성(Assistant Professor, Division of Mechanical & Automotive Engineering, Kongju National University) | Yong-Thung Cho Corresponding author