The Firefighter II candidate shall correctly define in writing the different material used in lightweight construction as well as identify lightweight construction components, describe their reaction to fire and truss locations found in structures.
ENABLING OBJECTIVES
The Firefighter II candidate shall identify in writing, what is considered lightweight construction and the materials used in the components of lightweight construction.
The Firefighter II candidate shall describe in writing, the reaction of lightweight structural components to fire.
The Firefighter II candidate shall identify in writing, the locations where trusses can be found in structures.
ENABLING OBJECTIVE#1
ENABLING OBJECTIVE#1
The Firefighter II candidate shall identify in writing, what is considered lightweight construction and the materials used in the components of lightweight construction.
Define the term “Truss construction.”
Discuss “surface to mass ratio.”
Discuss “Open web steel joists.”
Discuss “Wood trusses.”
Point out the different types of trusses.
Label the different parts of a truss.
Point out the difference between a steel truss and a wood truss.
Point out the difference between a steel truss and a wood truss.
Discuss the function of gusset plates to wooden trusses.
Define the term “Engineered wood structural member.”
Define the term “Plywood.”
Define the term “Oriented Strand Board.”
Discuss compression and tension forces as it relates to truss construction.
ENABLING OBJECTIVE#2
ENABLING OBJECTIVE#2
The Firefighter II candidate shall describe in writing, the reaction of lightweight structural components to fire.
Discuss the statement – “Our trusses are engineered.”
Discuss hazards associated with a “truss void.”
Discuss the fire characteristics of steel trusses.
Discuss the fire characteristics of wood trusses.
Discuss the fire characteristics of wooden I beams.
ENABLING OBJECTIVE# 3
ENABLING OBJECTIVE# 3
The Firefighter II candidate shall identify in writing, the locations where trusses can be found in structures.
Discuss floor trusses and the problems associated with them.
Discuss roof trusses and the problems associated with them.
ENABLING OBJECTIVE #3
ENABLING OBJECTIVE #3
The Fire Fighter II candidate shall correctly describe in writing why recognizing observations in reading smoke and the warning signs of hostile fire events is important.
1. Explain why reading smoke is important to evaluating the fires position within a building.
2. Explain how evaluating the volume of smoke assists in the understanding of the amount of fuel that is off-gassing in a given space.
3. Explain that the velocity of smoke is an indicator of pressure.
4. Describe the two things that can create smoke pressure.
a. Heat
b. Restricting the volume of smoke within a container
5. Explain how smoke thickens.
5. Explain how smoke thickens.
6. Discuss the fact that the greater the smoke density, the more likely a hostile fire event can occur.
7. Explain that the color of smoke will only indicate the type of burning material in a single-fuel fire.
Point out that smoke can tell the Fire Fighter which stage of burning is taking place.
APPLICATION
Divide the class up into suitable size work groups 3-5 candidates. Show them pictures of different fire scenarios and have them evaluate the smoke conditions. Assist them in recognizing the volume, velocity, density, and color of smoke for each picture.
Hydrogen Cyanide is more prevalent now than ever before due to the increased use of synthetics.
Hydrogen Cyanide is more prevalent now than ever before due to the increased use of synthetics.
It attacks our bodies through Oral inhalation as well as Occular and Dermal absorption. It is more lethal than CO and is more difficult to test for toxicity levels.
It is suspected of contibuting to the many of the FF Fatalities in the past originally thought to CO induced.
Fuel – UEL and LEL
Fuel – UEL and LEL
Reaction- Oxygen-Fuel effect
Ceiling layer-
High fuel/Low Oxygen
Floor Layer-
High Oxygen/Low Fuel
They meet at the reaction layer
Oxygen – Deficient or Enriched
What relationship does mass & density have on fuels?
What relationship does mass & density have on fuels?
Fuels are Synthetic now
Fuels have LESS MASS – they off-gas quicker!
Construction
Construction
Contents
Size
Ventilation
Fire protection systems
Type
Type
Insulation
Condition
Heat Flux
I-Joist
I-Joist
Glu-Lam
Glu-Lam
Finger-Joint
Panels
Panels
Wood Truss
Wood Truss
• As the surface temperature of wood increases due to fire exposure, flammable vapors are produced and a char layer (burnt wood) is formed on the external surfaces.
• As the surface temperature of wood increases due to fire exposure, flammable vapors are produced and a char layer (burnt wood) is formed on the external surfaces.
• In the presence of fire, these flammable vapors ignite and contribute to the fire.
• As the char layer gets thicker, it insulates the remaining unburned wood and slows the rate of vapor production, thereby slowing the charring process
American Forest & Paper Association- http://www.woodaware.info/index.html
American Forest & Paper Association- http://www.woodaware.info/index.html
Southern Building Components Association
http://www.sbcindustry.com/configurations.php
Type of fuel load
Type of fuel load
Size / Amount
Homeowners “padding” their homes:
Homeowners “padding” their homes:
Plusher carpet
Elaborate curtain & drapes
More / heavier furniture
Comfort accessories
“Bed, Bath & Beyond”
Increasing use of synthetic materials
Increasing use of synthetic materials
Tighter construction
Better insulation
Modern construction materials
Double/triple pane EE windows
Area
Area
Height
Configuration
Volume
Volume
Distance
Type
Influences fire spread
HVAC
HVAC
Sprinklers
Standpipes
Ceiling temps have increased from 1300 to 1600 degrees
Ceiling temps have increased from 1300 to 1600 degrees
BTU production > 18,000
(more than doubled)
Doesn’t necessarily change our tactics…
Doesn’t necessarily change our tactics…
How does “flammable range” factor in?
How does “flammable range” factor in?
To Read Smoke – you must be able to:
To Read Smoke – you must be able to:
Determine the stage of burning (early, growing, late)
Tell if the Fire is in Thermal Balance (smoke up and out, fresh air in).
Find out if the “box” is absorbing heat or not (Linear vs. Turbulent Smoke Flow)
Velocity (Pressure) = Heat, Volume, and Distance to fire
Density = Quality of burning – likelihood of “event”
Color = Stage of Heating, Distance, amount of “flaming”
Velocity
Velocity
Color
Volume
Density
Air Track
May be an indicator of pressure inside the container
May be an indicator of pressure inside the container
Pressure may be caused by heat or volume
If the velocity or pressure is a result of heat, the smoke will rise and loose velocity.
If the velocity or pressure is a result of heat, the smoke will rise and loose velocity.
If the velocity or pressure is a result of volume, the smoke will loose velocity but also maintain a neutral buoyancy.
Turbulent smoke is a potential
Turbulent smoke is a potential
indicator of the container not
being able to absorb more heat.
Laminar smoke is a potential
indicator of the container still
being able to absorb heat.
Smoke will become slower as distance from the seat of the fire increases.
Smoke will become slower as distance from the seat of the fire increases.
To locate the seat of the fire, compare smoke coming from several opening and determine which has the most turbulent smoke coming from the smallest opening
Heavy/light is an insufficient description
Heavy/light is an insufficient description
The department should have predetermined descriptions of smoke conditions in place in SOP’s
Darker- Hydrocarbon fuels
Darker- Hydrocarbon fuels
White- Incipient fire or great distance from the seat
Grey/yellow- Ordinary combustibles
Brown- Wood at or near ignition temperature possibly involving structural components
Light colored smoke may have large amounts of unburned fuel and may have travel some distance picking up moisture and depositing carbon.
Light colored smoke may have large amounts of unburned fuel and may have travel some distance picking up moisture and depositing carbon.
Dark smoke often indicates an under ventilated fire or hydrocarbon fuels.
May relate to amount of fuel
May relate to amount of fuel
May relate to pressure
Best as an indicator when coupled with other indicators
Ventilation controlled fires that near
the smoldering stage may produce
larger quantities of smoke.
Indicator of degree or location of
fire.
May result from amount of fuel in the smoke
May result from amount of fuel in the smoke
Heavy/light description is inadequate
Refers to how well you can see through the smoke.
Refers to how well you can see through the smoke.
Optically dense smoke may contain high concentrations of particulate matter.
“Black Fire” is the term we give to High Volume, High Velocity, Extremely Dense, Black Smoke.
It is the sure sign of impending flashover – VENT & COOL are your only choices.
Is there a chance of survival in a compartment that is producing black turbulent smoke?
Is there a chance of survival in a compartment that is producing black turbulent smoke?
Are rescue efforts feasible?
The maximum survivable (wet) temperature
Container (most important factor)
Container (most important factor)
Thermal Balance
Weather
Firefighting efforts
Other factors?
Are conditions getting better or worse?
Are conditions getting better or worse?
Classify the Fire:
Classify the Fire:
Consider that:
Consider that:
One hostile event can - and usually will - lead to another event.
Communicate your observations.
Warning Signs are not always visual – use your KNOWLEDGE and EXPERIENCE.
TRUST YOUR INSTINCTS…
When you open a door or window - watch what the smoke does…and what THE FRESH AIR DOES!
When you open a door or window - watch what the smoke does…and what THE FRESH AIR DOES!
In poor visibility - watch the smoke in front of your light - it will give you some clues
In poor visibility - watch the smoke in front of your light - it will give you some clues
A 5-second change in any key factor means an event has taken place – the key is to define what event has taken place and to forecast what will likely happen next.
A 5-second change in any key factor means an event has taken place – the key is to define what event has taken place and to forecast what will likely happen next.
“The garbage man doesn’t get excited when he turns the corner and sees trash, and you shouldn’t get excited when you turn the corner and see fire.”
“The garbage man doesn’t get excited when he turns the corner and sees trash, and you shouldn’t get excited when you turn the corner and see fire.”
