DIN ETS 300019-1-4/A1-1998 设备工程学.电信设备环境条件和环境试验.第1-4部分:环境条件分类.非气候防护性固定设备.修改件1
Equipment engineering (EE) - Environmental conditions and environmental tests for telecommunications equipment - Part 1-4: Classification of environmental conditions; stationary use at non-weatherprotected locations; Amendment A1; English version ETS 3000