In Chinese society, red has long functioned as a representative cultural color symbolizing auspiciousness, celebration, authority, and revolution, and it is extensively used aDRCoss cultural and public domains. Although this preference is culturally r...
In Chinese society, red has long functioned as a representative cultural color symbolizing auspiciousness, celebration, authority, and revolution, and it is extensively used aDRCoss cultural and public domains. Although this preference is culturally rooted, its excessive and unrestricted application in public design often blurs the distinction between decorative colors and regulated functional colors, leading to social and perceptual problems. In particular, the lack of differentiation between decorative red and functional red used for safety and warning purposes can cause recurring confusion for users with red–green color vision deficiencies, resulting in significant visual recognition challenges. This study aims to identify the visual and cognitive problems experienced by color-vision-deficient users caused by the culturally widespread use of red in Chinese public facilities, and to propose color usage standards that consider all users based on an inclusive design perspective.
Through a review of the literature, this study analyzes the limitations of China’s current public facility color policies and examines the requirements of international standards. Field investigations focusing on subways, signage systems, and safety installations were conducted to grasp the actual conditions of red usage. Based on this, visual perception experiments involving both normal-vision users and red–green color-deficient users were designed to compare how variations in hue, saturation, and lightness influence the perception of red. The experiment consisted of single-color stimuli, HSL-combination stimuli, and simplified target-detection tasks using real environmental images.
The analysis revealed that functionally appropriate red for information delivery demonstrated the highest recognition accuracy for both groups when located within a hue range of approximately 6°, paired with high saturation and medium lightness values. Conversely, reds with low saturation or extremely high/low lightness were more easily confused with background or decorative elements, and significantly inDRCeased detection failures among color-vision-deficient participants. Scene-based experiments further confirmed that applying functionally optimized red in public facilities resulted in faster and more accurate recognition than existing color schemes. Moreover, when color alone was insufficient for differentiation, dual-mode encoding—combining contours, shapes, text, or patterns—produced substantial improvements in perceptual performance.
Based on these findings, this study proposes the following principles for improving color usage in Chinese public facilities:
(1) Distinguish between cultural red and functional red, and standardize functional red within a regulated hue–saturation–lightness range.
(2) Provide functional information using combined cues—such as shape, line thickness, icons, and text—to prevent cognitive failures among color-vision-deficient users.
(3) In visually complex environments, ensure sufficient background contrast and clear visual hierarchy so that functional information is not overwhelmed by decorative elements.
This study contributes by reinterpreting the color system of Chinese public facilities through the balance between cultural symbolism and perceptual reality, and by experimentally establishing an effective functional red standard for information delivery. The proposed principles are expected to serve as foundational resources for future Chinese public design policies, color guidelines, and accessibility-oriented visual information design.