Iyakar fashewar acetylene suna tsakanin 2.5% kuma 80%, yana nuni da cewa fashe-fashe na iya faruwa a lokacin da maida hankalinsa a cikin iska yana cikin wadannan iyakoki. Bayan wannan bakin kofa, ƙonewa ba zai haifar da fashewa ba.
Dalla-dalla, Acetylene maida hankali a kan 80% ko kasa 2.5% ba zai haifar da fashewa ba, har ma da tushen kunnawa.