GOST R 51330.11-1999 爆炸保护型电气设备.第12部分:按照最大试验安全间隙和最小点火电流,对燃气或蒸汽与空气的混合物进行分类
Explosionprotected electrical apparatus. Part 12. Classification of mixtures of gases or vapours with air according to their maximum experimental safe gaps and minimum igniting currents