Which of the following is NOT a characteristic of Clean Agents?

The correct choice identifies that clean agents do not leave a residue upon evaporation. Clean agents are specifically designed to suppress fires while minimizing damage to sensitive equipment and areas. One of their primary advantages is that they vaporize completely without leaving residues that can complicate clean-up processes after a fire event. This characteristic makes them particularly useful in environments such as data centers, museums, and other locations housing sensitive materials and electronics.

In contrast, the other characteristics highlight why clean agents are effective in firefighting applications. Their versatility for different fire classes demonstrates their ability to extinguish various types of fires, including those caused by flammable liquids and electrical equipment. Being electrically nonconducting ensures that they can be utilized safely around energized electrical equipment without the risk of short circuits. Their gaseous nature allows them to penetrate effectively and reach the combustion zone, ensuring better fire suppression while avoiding collateral damage to the surrounding environment.