1981年部颁《农村电话线路工程施工及验收技术规范》第54条、第229条和有关规定,通信明线线路跨越铁路的跨越角不得小于45°;通信明线线路之间,其交越角度不得小于30°;以及通信明线与高压输电线路交越时,交越角度应接近90°。如确有困难,与长途一级通信明线线路的交越角不得小于45°;与长途二级通信明线线路的交越角不得小于30°。 1981, the ministerial “rural telephone line construction and acceptance of technical specifications,” Article 54, Article 229 and the relevant provisions of communication lines across the railway line spanning no less than 45 °; Less than 30 °; and crossover of communication bright line and high voltage transmission line, the crossing angle should be close to 90 °. If there is indeed any difficulty, the crossing angle with the long-distance communication Ming Xian line shall not be less than 45 °; the crossing angle with the long-distance secondary communication Ming Xian line shall not be less than 30 °.