Home / Standards / GB/T 43991-2024 GB/T 43991-2024 Active Service specifications for operation and maintenance of urban tunnel 城市隧道运维服务规范 Standard Type GBT ICS 93.060 CCS P21 Status 现行 Issue Date 2024-04-25 Implementation 2024-11-01 Responsible Dept 国家标准委 Drafting Unit N/A