Which stored-pressure extinguisher is suitable for Class C fires?

The correct choice for a stored-pressure extinguisher suitable for Class C fires is the carbon dioxide extinguisher. Class C fires involve electrical equipment, and extinguishing agents must be non-conductive to safely put out the fire without risking electric shock.

Carbon dioxide extinguishers work by displacing oxygen and smothering the fire while not leaving any residue that could potentially damage sensitive electrical equipment. This makes them ideal for Class C fires, as they effectively reduce the chances of re-ignition by eliminating the oxygen necessary for combustion.

Water-mist extinguishers, while they can be safer than water for certain incidents, are typically not recommended for use on electrical fires because water is a conductor of electricity. Foam extinguishers are designed for liquid fires and would also pose a risk when used on electrical equipment due to their potential conductivity. Dry powder extinguishers can be effective on Class C fires, but their use may not be as practical or as efficient for certain situations compared to carbon dioxide. Carbon dioxide extinguishers are thus the preferred choice for addressing Class C fire hazards effectively and safely.