Home / Standards / GB/T 17771-1999 GB/T 17771-1999 Abolished Earth-moving machinery--Falling-object protective structures--Laboratory tests and performance requirements 土方机械 落物保护结构 实验室试验和性能要求 Standard Type GBT ICS 53.100 CCS P97 Status 废止 Issue Date 1999-06-14 Implementation 1999-11-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A