ABSTRACT

Steps and stairs arc common features in our day-to-day living and working environment-found outside, in public parks, busy urban strcetscapes, individual building sites, and within every home. Unfortunately, the occurrence of accidents on or around steps is thus inevitable. A failed visibility to see or recognize a step remains the most common attribute in these accidents. Surprisingly, appropriate methods for examining and quantifying step visibility have yet to be established. In this research, sensory scales of step visibility were created in order to examine the effects of three factors on step visibility in sensory testing methods; visual characteristics of steps, observation distances from steps and observation actions while viewing step. Results revealed that step visibility tends to decline as observation distances increase, and the quality of step visibility varies based on the unique and individual visual characteristics of a each step. Moreover, we assumed that step visibility has a correlation with horizontal deviation, vertical deviation, and surface roughness of steps, and relative pattern size on both upper and lower landings, confirming that relative rating of step visibility changes and are based heavily on observation distances.