Firefighter Aptitude and Character Test (FACT) 2025 – 400 Free Practice Questions to Pass the Exam

Class D fires are specifically associated with combustible metals, which are unique in their properties and behaviors when ignited. Metals such as magnesium, titanium, sodium, and potassium can burn at extremely high temperatures and often react vigorously with water or other substances. This makes their combustion distinct from fires involving flammable liquids, gases, or ordinary combustibles.

The primary risk with Class D fires is the nature of the metals themselves, which can ignite and spread quickly, leading to intense fires that can escalate rapidly if not properly managed. Firefighting methods for Class D fires are specialized; for instance, water is not suitable as it can exacerbate the fire due to chemical reactions. Instead, dry powder extinguishing agents specifically designed for metal fires are necessary to suppress them effectively.

Understanding the characteristics of Class D fires and their associated risks is crucial for firefighters because it informs their approach to extinguishing these types of fires safely and effectively, ensuring that they are prepared with the proper techniques and tools.