Evaluation of Pictograms in Dynamic Lane Control Systems in the Republic of Korea

Pictograms have increasingly been used in electronic message display boards around the world as part of the intelligent transportation systems because they provide drivers with a clear and precise message that is easy to understand. This article reports on an evaluation of pictograms for a dynamic traffic control system in Seoul, Republic of Korea. In this study, some of the pictograms developed in an earlier study were redesigned and transferred to an actual variable message sign for a field test. In addition, drivers' perceptions of these pictograms were also elicited from a convenient sample to provide useful information to assist in the final selection of the pictograms. The study found that most of the pictograms were quite easy to comprehend. However, pictograms depicting accidents performed poorly, with only 10.0% and 43.5% of the participants correctly identifying the message conveyed by the European design and the existing ROK design, respectively. The pictograms depicting congestion and traffic incidents also performed moderately, with only 45%–55% correctly identifying the message conveyed. Finally, the European design for snow warning performed poorly (17.5% correct), whereas the ROK design performed relatively well (75.5% correct).