Study on the Influence of Guide Sign Margin on Visual Recognition Effect

With the progress of urbanization, underground and semi-underground interconnections have become increasingly common. This has led to the installation of more guide signs in tunnels, where limited space often limits the height of these signs. Therefore, it is necessary to lower the height of the guide signs in such cases. The height of a guide sign is determined by the combination of text height and sign margin. The height of the text has been extensively studied, and there are established standard guidelines. This paper delves deeper into the correlation between sign margin and visual recognition impact of signs through driving simulation, and identifies minimum and recommended sign margin values. In terms of subjective perception, with the decrease of margin, the visual recognition effect of the wayfinding sign gradually deteriorates; In terms of objective visual distance, there was no obvious difference in the visual distance of different margin guiding signs. The margin of the sign can be adjusted according to individual requirements. The minimum value is 0.1 times the text height, while the recommended value is 0.2 times the text height. These research findings can help address spatial constraints for directional signs.