Firefighter Fire Behavior and Suppression 2 — Questions and Answers
Question 1: What term describes the rapid spread of fire across the unburned gases collected at the ceiling of a compartment?
- Rollover (Correct answer)
- Backdraft
- Flashover
- Conduction
Correct answer: Rollover
Rollover (flameover) is the ignition and rapid spread of flame through the unburned gases accumulated at the ceiling.
Question 2: Which class of fire involves energized electrical equipment?
- Class A
- Class B
- Class C (Correct answer)
- Class D
Correct answer: Class C
Class C fires involve energized electrical equipment and require a non-conductive extinguishing agent.
Question 3: What is the primary extinguishing mechanism of water on a Class A fire?
- Smothering oxygen
- Cooling and heat absorption (Correct answer)
- Chemical chain interruption
- Saponification
Correct answer: Cooling and heat absorption
Water primarily extinguishes Class A fires by absorbing heat and cooling the fuel below its ignition temperature.
Question 4: A firefighter notices smoke puffing in and out of a closed door with no visible flame. This sign most likely indicates risk of:
- Flashover
- Backdraft (Correct answer)
- Rollover
- Pyrolysis
Correct answer: Backdraft
Pulsing or breathing smoke around openings signals an oxygen-starved compartment at risk of backdraft.
Question 5: Which method of heat transfer moves heat through direct physical contact between materials?
- Convection
- Radiation
- Conduction (Correct answer)
- Combustion
Correct answer: Conduction
Conduction transfers heat through direct contact between materials, such as along a metal beam.
Question 6: What does the acronym in the fire tetrahedron add beyond the classic fire triangle?
- Smoke
- Chemical chain reaction (Correct answer)
- Pressure
- Pyrolysis
Correct answer: Chemical chain reaction
The fire tetrahedron adds the chemical chain reaction to fuel, heat, and oxygen.
Question 7: Which extinguishing agent works best on a Class D combustible metal fire?
- Water
- Dry powder agent (Correct answer)
- CO2
- Foam
Correct answer: Dry powder agent
Dry powder agents are designed for combustible metals; water can react violently with burning metals.
Firefighter Fire Behavior and Suppression 2
What term describes the rapid spread of fire across the unburned gases collected at the ceiling of a compartment?