Home / Standards / GB/T 40621-2021 GB/T 40621-2021 Active Drawing method of cloud-to-ground lightning density distribution map 地闪密度分布图绘制方法 Standard Type GBT ICS 91.120.40 CCS M04 Status 现行 Issue Date 2021-10-11 Implementation 2022-05-01 Responsible Dept 国家标准委 Drafting Unit N/A