This paper deals with tapping noise produced on the floors in a reinforced concrete building which has five floors and seventy rooms as shown in figure 1. A tapping machine was used to generate tapping(impact) noise on a floor. Five positions setting a tapping machine on the floor in the source room, and setting a microphone above the floor in the receiving room were selected to measure impact sound level as shown in figure 4. A sound level meter, an one-third octave-band pass-filter and a level recorder were used to measure impact sound level of the floor.
The sound levels generated by impact of the center floor were higher than those generated by impact of nooks and corners above the floor in low frequency range as shown in figure 6. Noise level generated by the impact in the lower floor of tapping floor was higher than that of the upper floor as shown in figure 8, and 9. Difference of interior materials used gives a little effect on the room noise.