Use a Class A or dry chemical extinguisher if you have cut the power. If you are able to cut the power to the source completely, then you have turned the Class C electrical fire into a standard Class A fire.[13] In this case, you can use a water-based Class A extinguisher in addition to the previously mentioned extinguishers.
o Class A extinguishers and multipurpose dry chemical extinguishers are actually recommended in this scenario because CO2 extinguishers run a higher risk of the fire smoldering and reigniting once the CO2 dissipates.[14] CO2 extinguishers can also cause respiratory problems in confined spaces such as houses or small offices.[15]