Subjective Evaluation of Floor Impact

Abstract

Although much work has been undertaken in describing and quantifying the aspects that generate general sound annoyance, little research has been done investigating people's perception of noise within residential buildings. To efficiently and economically control noise, noise annoyance must be evaluated and explained as a comparable quantity. This study has been undertaken to measure loudness and noisiness of floor impact noise obtained from similar floor slab structures with three different impact isolators. The purpose of this study is to provide a reliable method to subjectively evaluate floor impact noise. Floor impact noises generated by bang and tapping machines were measured through dual microphones on the ear of a human head. Matching and magnitude estimation techniques for noise evaluation were used to investigate perceptual differences of the impact noises from apartment floors. Results presented in this paper on noise levels are based on the difference of noisiness between steady-state noise and intermittent noise. This study shows a 3 dB level increase within a 5 sec intermittent noise signal with 3 impact sources in the signal. However the tapping noise seems not to have the same effect because it was perceived as steady-state noise 4 dB lower on average. It was found that bang machine noise is perceived to be louder and noisier than that of a tapping machine. From the results of the experiments, the matching and magnitude estimation techniques are considered as a reliable method to subjectively evaluate noise.