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Abstract
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BACKGROUND: Road sign symbols have facilitated local and foreign travel by road for more than a century. Despite their long-standing use, many problems associated with their design adversely impact comprehension and legibility.
METHOD: To assess their current effectiveness, the design and worldwide application of thousands of these symbols were examined according to established criteria for sound symbol design. Analysis: Design issues explored ranged from addition of color and text to placement of prohibition bars to arrangement of multiple symbols on a sign to merits of mandatory vs prohibitory messages to alternative depictions of specific images, such as for ferries, cycle streets and disabled pedestrians.
RESULTS: The problems identified include unsuitable symbol size, line width, contrast, perspective, types of detail and image content. Numerous examples of symbol use and misuse are illustrated for warning, regulatory and facilities/services signs and for supplementary plaques. Guidelines, including a sequential-component approach, are offered for designing symbols that possess clear messages and high legibility.
CONCLUSIONS: According to the examples and advice offered herein, current symbols may be assessed for legibility and message content and be redesigned when necessary and designers of new symbols may avoid the mistakes of the past. To improve road safety, more symbols and their definitions must be standardized across national borders.
Language: en |