Two-line external scaffold is the type that is widely used in ring lock scaffolding system. Its standing braces shall be accurately located at positions and the erection of them shall be in pace with that of the whole construction process. The erection height limitation of standing braces at any one time in ring lock scaffolding system shall not be two lifts higher than the adjacent tie members.

What’s more, tie members, which can not be dismantled at will, shall be set at regulated positions according to the increasing height of scaffolds.

There are also specific requirements for erection of the working platform in the ring lock scaffolding system; firstly, the working platform shall be fully set with scaffolding boards.

Secondly, the external side of the platform shall be set with toeboards and guarding handrails which can be set with upper and middle transverse tubes on standing tubes on each working platform at ringlock joints with heights of 0.5m or 1.0m and a close mesh safe net shall be hanged all over the external side.

Last but not least, the space between working platform and the main building body shall be set with inside safe nets.