NFST Fire Behavior and Science Flashcards
6 cards from real NFST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 NFST Fire Behavior and Science flashcards as text
What is the minimum oxygen concentration required to sustain flaming combustion?
Answer: 16%
Flaming combustion generally requires at least 16% oxygen concentration to sustain itself.
Which of the following best describes 'flashover' in a structure fire?
Answer: When all combustible surfaces in a room ignite nearly simultaneously
Flashover occurs when all combustible surfaces in a compartment reach ignition temperature and burst into flame almost simultaneously.
The three components of the fire triangle are fuel, heat, and which third element?
Answer: Oxygen
The fire triangle consists of fuel, heat, and oxygen — remove any one and the fire will extinguish.
What type of heat transfer occurs when heat moves through direct contact between objects?
Answer: Conduction
Conduction is heat transfer through direct physical contact between materials.
Which class of fire involves energized electrical equipment?
Answer: Class C
Class C fires involve energized electrical equipment and require non-conductive extinguishing agents.
Backdraft is most likely to occur when a fire in a closed compartment receives a sudden influx of what?
Answer: Oxygen
Backdraft happens when a smoldering, oxygen-starved fire suddenly receives a fresh supply of oxygen, causing a rapid explosion.