Relationship of weighted acceleration levels between the ground surface and the floors of a wooden house

For evaluation of vibration which is transmitted to a human body, it is desirable to measure the vibration on the surface at the point of contact with a human body. International standard ISO2631‐2 describes measurement/evaluation methods of vibration in a house. In Japan, the ground vibrations caused by road traffic, factory facilities, and construction work have been regulated by law so that the life environment inside of a house can be kept in good condition. However, the regulation law is applied to vibrations measured on the ground surface. The magnitude of vibration on the floor of a house is usually estimated by adding a value of 5 dB to that on the ground surface. This value is a median value of the difference of magnitude of vertically frequency‐weighted acceleration between the second floor of a wooden house and the ground surface near the house. The author will compare recently measured data with these data because the amplification value was obtained about 20 years ago and the construction of the house has been changed. Moreover, the difference of the vibration magnitude between that which was estimated by the ISO combined curve and that which was estimated by the conventional curve will be discussed based upon the data measured in the field survey.