Home / Standards / GB/T 9862-1988 GB/T 9862-1988 Active Method for determining the speed and average gradient of black-and-white aerial camera films 黑白航空照相胶片感光度和平均斜率测定方法 Standard Type GBT ICS 37.040.20 CCS G80 Status 现行 Issue Date 1988-09-20 Implementation 1989-05-01 Responsible Dept 中国石油和化学工业联合会 Drafting Unit N/A