Firefighter Practice Exam

What is a common ignition source that can cause a fire when fuel vapors are present?

1. Cold temperature

2. Friction

3. Open flame

4. Electric spark

The correct answer is: Open flame

The presence of fuel vapors creates an environment where ignition sources can lead to a fire. An open flame is particularly dangerous because it has a direct, sustained source of heat capable of igniting flammable vapors immediately upon contact. When flammable vapors mix with air in the right proportions, they can catch fire instantaneously if exposed to a flame. While other potential ignition sources, like electric sparks or friction, can also ignite fuel vapors, an open flame is notable for its visibility and intensity. It is common in various settings, including kitchens, maintenance areas, or in situations involving combustibles. This makes understanding the danger of open flames crucial for fire safety and prevention measures, especially in environments where flammable materials are present.