A.按在最大試驗(yàn)安全間隙分級(jí) B.按最小點(diǎn)燃電流分級(jí) C.按引燃溫度分組 D.按氣體混合物特性分級(jí)
A.5cd/㎡,300cd/㎡ B.5cd/㎡,200cd/㎡ C.10ed/㎡,200cd/㎡ D.10cd/㎡,300cd/㎡
A.1.00h,1.00h B.1.00h,1.50h C.1.50h,1.00h D.1.50h,2.00h