Pipelines

The pipelines shapefile was digitized from Ai graphic files, where individual lines were traced from PDFs of individual county maps provided by the National Pipeline Mapping System(NPMS). Due to the sensitive nature of this data, the maps that were made available through NPMS are not precisely accurate and are intended for use at a county or regional scale.本管道shapefile由Ai图形文件数字化生成，其中各管线均由国家管道测绘系统（National Pipeline Mapping System, NPMS）提供的各县级地图PDF文件描摹绘制。鉴于该数据具有敏感性，NPMS所提供的地图并非精确无误，仅适用于县级或区域级尺度的应用。