V. Ratanavaraha, S. Jomnonkwao

Pages: 109-118

Abstract
Long distance driving exposes drivers to microsleep or drowsiness that can possibly cause run-off-road accidents. It is therefore, crucial to install safety devices for alerting drivers in order to prevent accidents. This study aimed to test the efficiency of shoulder rumble strips (SRS), which is renowned as a safety device, designed for preventing accidents. The study determines if SRS are statistically significant in creating high alarm levels to warn unmindful or drowsy drivers. It also examines the efficiency differences among the three types of SRS: profiled; milled-in; and transverse. The study findings showed that the three types of SRS can increase noise levels, ranging from 9.97 dBA to 17.47 dBA, which are enough to alert the drivers. Results revealed that efficiencies of both profiled and transverse SRS were significantly similar, whereas milled-in SRS showed efficiency differences at all speeds and reported the lowest increase in noise level.

Keywords: shoulder rumble strip; run-off-road accident; microsleep; ANOVA