Block Overlap

It is an adequate distance that has to be kept clear beyond FSS (First Stop Signal) before granting line clear, not less than 180 meters (MAS).

In MAS (Double Line): Block overlap is from the Home signal to BSLB (Block Section Limit Board) or the outermost facing point.

In MAS (Single Line): Block overlap is between the Home signal and the Opposite Advanced Starter/SLB (Starter Limit Board) or the outermost facing points.