Determination of sound transfer coefficient of boron added waste cellulosic and paper mixture panels

When the studies about the effects of noise on the human health were investigated, it was determined that the noise has physiological, pathological, psychological and psycho-social results and affects sense organs, circulatory, respiration, digestion, excretory and nervous systems in terms of physiology. In this research, a sound insulation study was carried out in order to minimize the negative effects of sound on the people who work in enclosed spaces. For sound insulation, two unreflecting rooms were constructed by using boron-added cellulosic and pulverized paper mixture. However, values (sound transfer coefficient) for the measured absolute values and the NRCs (Noise Reduction Coefficient) for 250, 500, 1000, 2000, 4000, 8000 Hz frequencies which are the most sensitive ones for human ear were calculated. The material used in the study was so efficient for high frequencies. The NRC and value were obtained for clean paper mixture as 0.46 and 0.38, respectively and for waste paper mixture as 0.34 and 0.38, respectively with 3 cm thickness; for clean paper mixture as 0.55 and 0.81, respectively and for waste paper mixture as 0.31 and 0.72, respectively with 5 cm thickness. The mixture with 5 cm thickness can be easily used inside the walls of critical utilization areas like office, house, hospital, etc. that exist near and/or inside the traffic, bazaar, park, children park areas.