What advantage does CO2 have over a dry chemical extinguisher?

Carbon dioxide (CO2) extinguishers offer a significant advantage in that they do not leave a residue after use, making cleanup much simpler. This is particularly beneficial in scenarios involving delicate equipment or environments where cleanliness is paramount, such as electronic labs or offices with sensitive devices. Additionally, CO2 is non-corrosive, which means it won't damage electrical contacts or components, making it a preferred choice for fires involving electrical equipment.

The effectiveness of CO2 in confined spaces where suffocation rather than contamination is the concern adds to its utility. Since the gas is also non-conductive, it can be safely used on live electrical fires without the risk of conducting electricity and causing further issues.

In contrast, options emphasizing residue left behind or general fire types do not accurately represent CO2's advantages compared to dry chemical extinguishers, which may leave a powdery residue and are not as effective on certain classes of fires.