Assessment of risk of tripping before and after crossing obstacles under dimmed lighting conditions

Tripping and falling are common at work. Investigating the perceived risk of tripping is important for the safety of workers.

To test the hypotheses that the perceived risk of tripping is affected by obstacle depth, obstacle height, number of obstacle, and light location under dimmed lighting conditions.

A walkway with one to three obstacles in the middle was prepared. Each obstacle had a height of 0, 5, or 10 cm and a depth of 1 or 10 cm. The laboratory was dimmed with only one light either at the beginning, the midway, or at the end of the walkway. The perceived risk of tripping (PRT) was measured both before and after the participant walked through the walkway. A rating of gait disturbance (RGD) to each participant upon crossing the obstacle was also recorded.

The PRT measured both before and after the walk were between "almost no" to "medium" risk levels. The RGD was affected significantly by the location of the light, obstacle height, obstacle depth, and number of obstacle.

The location of light significantly affected the PRT both before and after the participants walked. The participants perceived a higher risk of tripping and had a relative high probability of foot-obstacle contact when the light was behind than when the light was in the front.