This study investigates characteristics of the perception threshold and sensory evaluation of vertical vibration. A questionnaire was prepared to determine a suitable category from 5 categories in a vibration test. Scatters in perception threshold and sensory response are evaluated based on the probability of a category being chosen for each experimental object vibration, and the relationship between them and physical elements of vertical vibration are investigated. As a result, a common characteristic on frequency to perception threshold and sensory response is found. Response probability is constant to acceleration under 10Hz and less severe as frequency becomes higher than 10Hz. The acceleration range and scatters of response differ depending on the types of sensory evaluation. The change in sensory evaluation of the subjects who perceive a vibration is investigated based on a relationship between perception threshold and sensory response. The result shows that they are evaluated from independent points of view, because there is a range that the subjects feel very small or no discomfort etc. to perceptible vibration.
