Ch. 7: Reading Smoke Flashcards
Smoke leaving a structure has four key attributes:
volume, velocity (pressure), density, and color
The product of incomplete combustion that includes an aggregate of solids, aerosols, and fire gases that are toxic, flammable, and volatile.
smoke
What can help the ISO determine the size and location of the fire, the effectiveness of fire streams, as well as the potential for a hostile fire event like a flashover?
A comparative analysis of the attributes of smoke.
What is a by-product of incomplete combustion, specifically particulates (solids) that were suspended in a thermal column?
Smoke
What is an explosive aggregate of solids, aerosols, and gases?
smoke
Good thing: The products of combustion are minimized because the burning process is more complete.
“Open flaming”
What happens when materials can only absorb so much heat before it starts to break down and “off-gas” without flaming?
Smoke becomes flammable.
_________ is extremely flammable and ultimately dictates fire behavior in a building.
Smoke
What are the two triggers that may cause accumulated smoke to ignite?
The right temperature and the right mixture.
What will the ignition of flame spread across surfaces of contents do to fire?
The fire spreads with the smoke flow.
What tells you how intense the fire is about to become as opposed to how bad it currently is?
Watching the smoke.
An event that can catch firefighters off guard and endanger them: flashover, backdraft, smoke explosions, and rapid fire spread.
Hostile fire event
All gases reach their ignition temperature at virtually the same time due to rapid heat buildup in the box.
Flashover
What event will show warning signs of turbulent smoke flow, rollover, and autoignition outside?
Flashover
What is suspected when there is sucking or puffing witnessed near a box?
Backdraft
What event happens when a spark or flame is introduced into trapped smoke that is below its ignition temperature but above its flashpoint?
Smoke explosion
What event happens when smoke reaches sustaining temperatures that are above the fire point of prevalent gases?
Rapid fire spread
The ISO must study the warning signs of hostile fire events and watch for the signs as part of the reading smoke process.
The ISO must study the warning signs of hostile fire events and watch for the signs as part of the reading smoke process.
Warning signs -
- Turbulent smoke flow
- Rollover
- Autoignition outside
Flashover
Warning signs -
- Yellowish-gray smoke
- Bowing, black stained windows
- Signs of extreme heat on outside of box/compartment
Backdraft
Warning signs -
- Smoke that is being trapped above the fire
- Signs of a growing fire
- Signs of smoke starting to pressurize
Smoke explosion
Warning signs -
- Increase in smoke speed
- Smoke flowing from hallways and stairways faster than a firefighter can move
Rapid fire spread
What type of approach must an ISO take by watching the four smoke attributes?
A proactive approach
What can help the ISO understand fire behavior?
By comparing the smoke volume, velocity, density, and color.