Reading Smoke Flashcards
Smoke is what?
Fuel
How much of smoke is particulate?
70%
What are the key smoke attributes?
- Volume
- Velocity (Pressure)
- Density
- Color
What is the flammable range for CO?
12-74%
What is “Black” fire?
High volume, high velocity, extremely dense, black smoke
What does “Black” smoke indicate?
Impending flashover
What is black, thick, and fast smoke mean?
Heat and explosive
What is black, thin, and fast smoke mean?
Flame is nearby
What is white smoke with speed mean?
Hot, but fire is distant
What is smoke that is uniform in speed and color from many places mean?
Deep seated fire
What does “Brown” smoke mean?
Burning of unfinished wood, structure fire
What does turbulent smoke indicate?
Flashover
What is the most important factor when looking at smoke?
Density
Reading smoke uses three concepts, what are they?
- Smoke is Fuel
- The Fuels Have Changed
- Smoke has “trigger points” which can cause smoke ignition
Smoke is made up of?
- Particulates
- Aerosols
- Gases
Particulates in smoke is made up of?
- Carbon
- Dust
- Minute Fibers
Aerosols in smoke is made up of?
- Water Vapor
- Hydrocarbons
What are some of the gases in smoke?
- Carbon Monoxide
- Hydrogen Cyanide
- Benzene
- Acrolein
What was the change in fuels?
- Went from natural to synthetic products.
- Changed to low-mass and high surface-to-mass products
What are “trigger points” of smoke?
- Right temp
- Right mixture
Guidelines to reading smoke?
- Reading smoke is by no means absolute science
- Reading smoke is an outside activity
- Comparison of smoke issuing from various openings is key
- Reading smoke is just that: read the smoke-not the flames
Flames are at there ______ potential, the future of the incident is in the _______.
Flames
Smoke
What are the 3 steps to reading smoke?
- Inventory and compare the four key attributes of smoke (Volume, Velocity, Density, Color)
- Evaluate other factors such as the building size and weather influences
- Determine the rate of change (how fast are the smoke attributes changing)
- Tells how much fuel has off-gassed within a given size box
- Gives an impression
- Helps us understand velocity
Volume
- How fast is the smoke leaving?
- Can indicate volume or heat
- Helps find the location of the actual fire
Velocity
Smoke velocity can be _____ pushed or ______ pushed.
- Volume
- Heat
Smoke that leaves a building and is quick to slow or dissipate is what type of pushed smoke?
Volume
Smoke velocity that leaves and keeps its energy and speed will alway indicate what type of push smoke?
Heat
When comparing smoke velocities and heat rise levels to help locate the seat of the fire, what is needed to make this work?
To compare only like sized openings
How does the size of the opening effect the smoke?
The speed in which it can leave
- Quality of burning
- Severity of event
- Continuity of fuel
- Air flow to the fire has been restricted (burning is incomplete)
Density
The thicker the smoke the more ______ it has become.
Explosive
What does smoke color tell us?
- Stage of heating
- Location of the fire in the building
What does brown smoke tell us?
Transitioning from contents to structure fire.
Unfinished wood is being heated
Structural integrity is being lost
What can change the meaning of the four attributes of smoke?
- Building size
- Number of ventilation points
- Weather
