1　General

1.0.1　This code is developed to ensure that the investigation and surveying for 330kV-750kV overhead transmission lines comply with relevant national laws，regulations，guidelines and policies，suit projectspecific natural engineering conditions，these lines are safe，reliable，technically advanced and applicable，cost effective，with high return on investment and environmental friendliness.

1.0.2　This code applies to the survey，geotechnical investigation，engineering hydrological investigation and surveying，and engineering meteorological investigation and surveying at stages of feasibility study，preliminary design and detailed design of newly constructed or expanded 330kV-750kV overhead transmission lines.This code is not applicable to the investigation and surveying of large crossing overhead transmission lines.

1.0.3　The investigation and surveying of overhead transmission lines shall be divided to suit the design stages，consisting of investigation and surveying at feasibility study，preliminary design and detailed design stage.

1.0.4　All measuring instruments and equipment used for engineering investigation and surveying shall be periodically calibrated in accordance with the national meteorology laws，and all professional applications used shall be certified or verified.

1.0.5　Original engineering investigation and surveying records must be authentic and accurate，and the references collected shall be verified.

1.0.6　This code specifies the basic requirements for investigation and surveying of 330kV-750kV overhead transmission lines.Where this code is in contradiction with relevant provisions of national laws or administrative regulations，the latter shall prevail.

1.0.7　In addition to this code，the engineering survey，geotechnical investigation，engineering hydrological investigation and surveying，and meteorological investigation and surveying of 330kV-750kV overhead transmission lines shall comply with relevant national standards in force as well.