Article 3.3.3 of the Code for Barrier-free Design (GB 50763-20 12) stipulates that the entrance gradient of wheelchair ramp and flat slope with barrier-free entrance shall meet the following requirements: ① The ground gradient of flat slope entrance shall not be greater than1:20, and it shall not be greater than1:30 when the site conditions are good; (2) At the same time, steps and wheelchair ramp entrances and exits shall be set, and the gradient of wheelchair ramp shall comply with the relevant provisions in Section 3.4 of this specification.

According to the latest specification, the title "flat-topped entrance" was changed to "flat-sloping entrance".