Ko e moʻoni, ʻOku ʻuhinga ʻa e volatility maʻolunga ʻo e penisini ko e taimi ʻoku aʻu ai ʻene concentration ki ha tuʻunga pau, ʻe lava ke iku ʻa e fakafetuʻutaki ki ha ulo ʻoku ava ki he ignition pe fakaʻauha.
Ko e ʻikai ke ʻi ai ha ʻosikena ʻi ha ʻatakai ko e meʻa pe ia he ʻikai ke ne fakaulo ʻa e penisini. ʻI he tafaʻaki ʻe taha, concentrations ʻoku mahulu atu ʻi he fakangatangata ʻo e fakaʻauha ʻa e fakaʻauha, ka ʻi he ʻao ʻo e ʻokisikena, ʻOku taʻeʻamanekina ʻa e vela.