With communication line construction and maintenance as the link, this book introduces standards, norms and procedures at all levels for survey, construction and maintenance, providing standards and rules for workers in using labor protection supplies and instruments. Supplemented with typical cases in each section, it enhances readers understanding. To further ensure personal safety, this book also includes information on first aid and self-help and provides specific operation methods. This book is suitable for those engaged in construction and maintenance of communication lines and tower mast as well as the teaching of colleges, universities and vocational and technical schools.