5.2　Indoor Selection of Routing Scheme

5.2.1　When selecting the routing scheme indoors，the routing scheme determined through the design review at feasibility study stage shall be understood.

5.2.2　Where the routing scheme at the preliminary design stage deviates greatly from that of the feasibility study stage，topographic maps with the scale of 1∶50，000 or 1∶10，000 should be collected.When selecting the routing scheme indoors，the surveyors shall cooperate with the design personnel for scheme comparison and selection.

5.2.3　When selecting the routing scheme indoors，the surveyors shall analyze the distribution of national horizontal and elevation control points along the route and propose the scheme to be adopted.