New types of electro-dynamic vibration tables of vertical and horizontal directions for whole body at sitting and standing postures were devised. The tables could gener-ate various kinds of output wave forms (sinusoidal, random and shock vibration) with large amplitude and wide frequency range.

The levels of threshold and equal sensation of whole body for both vibrations were measured at sitting and standing in erect and relaxed states on various amplitudes in the range from 0.5 to 300 c/s and up to 60 dB (vibration acceleration level at 20 c/s).

The curves of threshold for vertical and horizontal vibrations consist of 5 or 4 straight lines withbending points respectively, and each slope of these lines had physical meaning of jerk, acceleration, velocity and displacement. In addition, there is a difference of vibration acceleration level between both thresholds by about 10 dB.

The contours of equal sensations for both vibrations above 5 c/s are composed of three lines with the slope of acceleration, velocity and displacement bending at 5 c/s and 60 c/s. Below 5 c/s, those of equal sensation for horizontal vibration show considerably lower values than those for vertical one.