A.關(guān)鍵機(jī)組故障率=（設(shè)備故障次數(shù)/設(shè)備總臺(tái)數(shù)）×100%
B.關(guān)鍵機(jī)組故障率=（單機(jī)設(shè)備故障停機(jī)次數(shù)/單機(jī)設(shè)備開動(dòng)時(shí)間）×100%
C.關(guān)鍵機(jī)組故障率=（設(shè)備故障停機(jī)時(shí)間/單機(jī)設(shè)備開動(dòng)與停機(jī)時(shí)間總和）×100%
D.關(guān)鍵機(jī)組故障率=（單機(jī)設(shè)備故障停機(jī)時(shí)間/單機(jī)設(shè)備開動(dòng)時(shí)間）×100%