Which of the following is NOT one of the three major components of smoke?

The correct answer is based on the understanding of the fundamental components of smoke produced during a fire. Smoke is primarily made up of particles, vapors, and gases.

Particles refer to the solid and liquid components that are suspended in the air, which include soot and other residues from the burning material. Vapors consist of gas formed from the evaporation of liquids, which may also arise during combustion processes. Finally, gases are the various chemical compounds that are released during burning, such as carbon dioxide and carbon monoxide.

Flames, on the other hand, are not a component of smoke. Instead, flames are the visible phenomenon that occurs when combustion is actively taking place. They consist of a mixture of hot gases and can lead to the production of smoke but are not classified as a component of smoke itself. Understanding the elements that compose smoke is crucial for fire behavior analysis and can help in understanding fire dynamics during firefighting operations.