What hazard class includes materials that can enhance the combustion of other materials?

The correct choice relates to Class 5, which encompasses oxidizers and organic peroxides. Materials in this class are of particular concern because they can significantly enhance the combustion of other materials. Oxidizers are substances that provide oxygen to support the combustion process and can cause fires or explosions when in contact with combustible materials.

For instance, substances such as ammonium nitrate and potassium chlorate are common examples of oxidizers. When these substances are introduced to a fire or heated, they can release oxygen and promote the burning of nearby materials that would not typically ignite in air.

Recognizing the properties of Class 5 materials is crucial for first responders, as it helps them to effectively assess hazards during incidents involving these substances and to implement appropriate safety measures to mitigate the risk of fire or explosion.