GB/T 39758-2021 in English

Analysis of the core content of the standard

Detailed explanation of key technical parameters

The standard clearly stipulates the three-dimensional structure of the braille dots: bottom diameter 1.0-1.7mm, center height 0.3-0.7mm, and the arc section must be maintained. In high-frequency use scenarios such as automatic teller machines and elevator control panels, it is recommended to use the upper limit size to enhance durability.

Implementation and application guide

Sign system design

The braille layout of stair handrails must meet the following requirements: extension section ≥300mm, and the direction of the text is parallel to the handrail axis. As shown in Figure 5, multi-story buildings should set up hierarchical guidance information at the end of the handrail to form a complete navigation chain in conjunction with the blind path system.

Controller Braille Configuration

Button controllers follow the "horizontal on top/vertical on the left" principle: Braille is located above the button when arranged horizontally, and on the left when arranged vertically. Rotary disc Braille should be in the same direction as ordinary text, avoiding diagonal or inverted arrangement.

Background of Standard Evolution

This standard adopts the translation method equivalent to ISO17049:2013. The main technical changes include: adding graphic annotations (Figures 1, 2, 4-6), refining blank area requirements, and strengthening outdoor application specifications. Compared with the 2000s version, new adaptability requirements for new interactive devices such as touch-sensitive surfaces have been added.

Material selection recommendations

• Durability: Wear-resistant materials such as stainless steel and engineering plastics are recommended
• Safe touch: The edges need to be rounded, with an R angle ≥ 0.5mm
• Environmental adaptability: UV stability and antifreeze properties should be considered for outdoor applications