Structural Fire Fighting Flashcards
Fire Dynamics
Energy is the capacity to perform work in the case of heat work means increasing a substance temperature
Kinetic energy
When heat is introduced to an object the molecules within the fuel begin to vibrate as the heat thermal energy increases these molecules vibrate more and more rapidly the fuse kinetic energy is the result of these vibrations in the molecules
Energy
Is measured in joules the unit of measurement for heat is the British thermal unit BTU a British thermal unit is the amount of heat required to raise the temperature of 1 pound of water by 1 degree Fahrenheit
Exothermic reactions
Reactions that emit energy as they occur
Endothermic reactions
Reactions that absorb energy as they occur
Fire triangle and tetrahedron
Fire triangle is oxygen fuel Heat
Fire tetrahedron is reducing agent fuel, oxidizing agent, Heat, chemical chain reaction
Ignition
Fuels must be in a gaseous state to burn there for solids and liquids must become gaseous in order for ignition to occur
Piloted ignition
Most common form of ignition and occurs when a mixture of fuel and oxygen encounter in external heat source with sufficient heat or thermal energy to start the combustion reaction
Auto ignition
Occurs without any external Flame or spark to ignite the fuel gases or Vapors
Auto ignition temperature
Is the minimum temperature at which a fuel in the air must be heated in order to start self sustain combustion the auto ignition temperature of a substance is always higher than its piloted ignition temperature
Products of combustion
Describe this heat and smoke while the heat from a fire is a danger to anyone directly exposed to it supposed to toxic gases found in Smoke and or lack of oxygen cause most fire Death smoke is an aerosol comprised of gases vapor in solid particles
Carbon monoxide
Is toxic flammable product of incomplete combustion of organic carbon containing material it’s colorless odorless gas present in almost every fire it is released when an organic material Burns in an atmosphere with limited supply of oxygen
Co combines with hemoglobin about 200 times more effectively than oxygen
Hydrogen cyanide
Toxic and flammable substance produced in the combustion of materials containing nitrogen also found in Smoke
The following materials produced hcn these materials are found in upholstered furniture, bedding, insulation, carpet, clothing
Hcn is 35 times more toxic than Co hcn is significant by product of the combustion of polyurethane foam used in many household furnishings
Carbon dioxide
Is is a product of complete combustion of organic materials it’s not toxic in the manner of Co + hcn but it displaces existing oxygen which creates an oxygen deficient atmosphere
Chemical energy
Chemical energy is the most common source of heat in combustion reactions
Mechanical energy
Friction or compression generates mechanical energy the movement of two surfaces against each other heat of friction that generates heat and or Sparks heat is generated when a gas is compressed
Radiation
Radiation is the transmission of energy as electromagnetic waves such as light waves radio waves or x-rays without an intervening medium
Radiant heat transfer primarily depends on the temperature of the heat source
Fuel known as the reducing agent
Most common fuels are organic containing carbon and other elements organic fuels can be divided into hydrocarbon best fuel such as gasoline fuel oil plastic cellulose-based materials wood in paper
Power
Is the rate at which energy transfers power is the heat release rate during combustion
Heat release rate
Is the energy released per unit of time as fuel Burns and is usually expressed in kilowatts heat release rate depends on the type quantity in orientation of the fuel
Gases
Gaseous fuels such as methane natural gas hydrogen and acetylene can be the most dangerous of all fuel types because they are already in the physical state required for ignition
Characteristics of common flammable gases
Methane natural gas ignition temperature 1004 degrees Fahrenheit
Propane 842 degrees Fahrenheit
Carbon monoxide 1128 degrees Fahrenheit
Flashpoint
Is the minimum temperature at which a liquid gives off sufficient Vapors to ignite but not sustain combustion in the presence of a piloted ignition source
Firepoint
Is the temperature at which a pilot ignition of sufficient Vapors will begin is sustain combustion reaction Flashpoint is commonly used to indicate the flammability Hazard of liquid fuels
Oxygen
Normally air consists of about 21% oxygen that energy release in fire is directly proportional to the amount of oxygen available for combustion
At normal ambient temperatures 68° Fahrenheit materials can ignite and burn at oxygen concentrations as low as 15%
Oxygen concentrations
Atmosphere having less than 19.5% oxygen is considered oxygen-deficient
In the atmosphere exceeds 23.5% that mysterious consider oxygen-rich represents an increase fire risk
Compartment fire development
All compartment fires begin in the incipient Stage is fuel limited fires once the fire reaches the growth stage the fire will either remain fuel limited if there is enough oxygen to support continued growth or the fire will consume all available oxygen and become ventilation Limited
Incipient stage
Test answer the High Castle is in the plume rise until they encountered the ceiling and then began to spread horizontally this flow of fire gases is called the ceiling jet
Incipient stage transition
A visual indicator that he fire is leave in the incipient stage is flame height when flames reached 2.5’ high radiated heat begins to transfer more heat then convection the fire will then entered the growth stage
Combustion Zone
Therefore when the fuel package is not in the middle of the room the combustion Zone the area where sufficient are is available to feed the fire expand vertically Andy higher plume results a higher Plumb increases the temperatures in the developing Hot Gas layer at ceiling level in increases the speed of fire development
Isolated flames
May move through the hot gas layer combustion of hot gases in the case that portions of the hot gas layer are within their flammable range and there is significant heat to cause ignition
The appearance of isolated flame is sometimes an immediate indicator of flashover
Rapid fire development
Refers to the rapid transition from the growth stage or early Decay stage to a ventilation limited fully develop stage among these events are flash over and Backdraft
Flashover rapid transition from the growth stage to the fully developed stage is known as flash over
FLASHOVER OCCURS DURING GROWTH STAGE
TEMP OVER 1100 DEGREES F
Significant indicator of flashover is ROLLOVER- where unburned fire gases that I have accumulated at the top of the compartment ignite and Flames propagate through the hot gas layer or across the ceiling
CO
The auto ignition temperature of CEO the most abundant fuel gas created in most fires is approximately 1100 degrees Fahrenheit
Survival fact
In IST testing conducted in 2013 has shown that the SCBA facepiece begin to fail after 5 minutes of exposure to a heat flux of 15 kilowatts per minute squared
Types of neutral plane
HIGH NEUTRAL PLANE - May indicate that the fire is in the early stages of development remember that high ceilings can hide a fire that has reached a later development stage a higher neutral plane can also indicate a fire above your level
Mid-level neutral planes could indicate that the compartment has not yet ventilated or that flashover is approaching
Very low-level neutral plane May indicate that the fire is reaching Backdraft conditions this occurrence could also mean that a fire is below you basement fire or lower story
Backdraft facts
The violence of the Backdraft depends upon the extent to which the fuel-air mixture is confined in the compartment the more confined the more violent the Backdraft will be
Needed fire flow
Offencive interior fire attack in a compartment or structure does not more than 50% involve the formulas less accurate and therefore less effective at a at involvement greater than 50% or 1 floors are determined to be greater than 1000 gallons per minute
Length times width divided by 3 times per cent involvement
Type 1 buildings
Most common fires in this type of construction are room and contents
Type 2 buildings
The most common form of type 2 construction are structures with metal framing members metal cladding in concrete block tilt slab walls with metal deck roofs Unprotected open web joist steel supports
Type 2 construction is normally used when fire risk is expected to be low or when fire suppression and detection systems are designed to meet the hazard load
Type 3 Construction
It’s common in older churches schools apartment buildings and Mercantile structures
This construction type requires that exterior walls be constructed of non-combustible materials typically masonary
Issues with this type of building concealed spaces
Type 4 construction often referred to as heavy Timber this construction type uses large Dimension Timber greater than 4 in 4 all structural elements
Any other materials used in construction and not composed of wood must have a fire resistance rating of at least one hour
Floors and rooster constructed of wood in Germany have no void or concealed spaces
Type 5 construction is commonly known as wood frame Construction
Single-family dwelling or residence is perhaps the most common example of this type of construction
A fire in this structure can quickly become ventilation limited most energy efficient homes are typically associated with class 5 Construction
Structural collapse
Traditionally taken the height of the structure and multiplying it by a factor of one and a half has been used to estimate the collapse Zone
Collapse hazards
Most collapses usually involve brick or masonry block and maybe structural components or veneer
Collapse potential increases in the growth stage as heat increases in the upper levels of the space and Flame spread stool and consumes the combustible structural members
In a Decay stage in during post depression activity collapse becomes likely due to the weakened state of structural members and the buildup of water
Nims operations
Branch organizational level having functional Geographic responsibility for major segments of incident operations
Division organizational level having responsibility for operations within a defined geographic area
Group organizational level equal to division having responsibility for a specified functional assignment at an incident for example ventilation Salvage water supply
Unit organizational level within the sections that fulfill specific support functions such as resources documentation demobilization
Reading smoke
Tar and carbon are the most common heated particles found in Smoke giving it the black color water moisture in heated gases give the smoke it’s white color
Light colored smoke for slow-moving smoke
Can indicate your smoke has travel distances from the origin a small amount of smoke from a large structure could easily be an indicator of a well seated fire inside
White smoke
Test question
Indicates that paralysis chemical change by heat is a recurring in areas adjacent to the main body of Fire
The light white color indicates moisture and gases are being released from the product
Brown smoke
Is common in mid-stage heating as moisture mixes with gases in carbons as paralysis increases
Brown smoke is an indication of burning wood weather unfinished found large lint addicts or unless we’re finished as found in structural wood members
Gray smoke
Indicates a combination of mixing it can be Mid stage with white brown or black or can be different smoke areas combined it can indicate smoke production changes from Mid-State Heating to high heat
Black smoke
Contains high quantities of carbon particles and is also an indicator of the amount of ventilation available at the seat of the fire the thicker the smoke the less clean-burning and less oxygen available as smoldering fire produces massive amounts of black smoke
Thin black smoke is fast-moving and indicates that the fires nearby
Neutral plane
A high neutro play May indicate that a fire is in the early stages of development a higher neutral plane can indicate you are further away from the seat of the fire
Neutral plane
When the neutral plane is roughly centered between the ceiling and the floor the fires beginning to be ventilation control and Flash over conditions are developing
A neutral playing close to the floor May indicate that the compartment room is reaching flash over conditions were that the fire is at a grade below the room being observed
Smoke movement
Floating or hanging lost its heat smoke is the same temperature as the air around it this characteristic is often found in air-conditioned buildings
Lazy smoke indicates a small early stage fire mostly containing moisture from the first stage of paralysis it could also mean a deep-seated fire in a large building where the smoke is cooling off as it travels significant distances
Smoke movement facts
When smoke fills the compartment it becomes pressurized
black smoke means that the fire has an open area travel by white indicates a filtered area of travel
Laminar smoke
Is heat pushed and not obstructed or ventilation Limited laminar smoke flow exits from openings near the active flaming fire
Rescue fact
If it is believed that people are alive and still savable in the structure use offensive strategy to rescue them if it is known that they are viable victims inside the structure then the two in two out rule does not have to be followed
Transitional attack
Based on information from n i s t to traditional offensive strategy should now include the option to apply water from the exterior of the structure as Crews Advance into the interior
As Crews deployed in charge hand line while preparing for interior attack water can be directed into the structure for initial not down at the discretion of the unit officer
Par
Icees must conduct personal accountability reports to check on the welfare of all firefighters on the scene every 10 to 20 minutes in accordance with the Department’s sop and G any one of the above conditions has occurred
Transitional attack
For the transition to be efficient and effective it must occur as soon as the need is recognized the IC must maintain current and accurate knowledge of the situation
Primary Search definition
Primary search it’s a wrap it but thorough search does reform either before or during fire suppression operations the search should Advanced towards those occupants would be in the most danger entry should also be made as close to that point as possible this area is typically above the fire in the rooms adjacent to the fire
Secondary research
Is conducted after the fires under control in the greatest hazards have been controlled Personnel other than those firefighters who conducted the primary research should conduct the secondary search it’s slower more thorough search that attempts to ensure that no occupants were overlooked
General traditional search
Systematic pattern such as left or right-handed search this type of search method is effective when entering a structure from a normal egress such as a door in the structure is compartmentalize into small rooms
These searches require the least amount of training and supervision to be performed*
VEIS- vent, enter, isolate, search
Utilize when it is suspected or probable that a victim is present in a specific room or compartment within the structure and there is a direct access point to enter the room typically a window
This procedure should only be initiated following a 360-degree sizeup of structure in the IC should consider risk assessment when making this assignment only areas that appear to be survivable an unlikely a fire extension should use this technique
Confinement
Smoke exiting the structure lazily typically indicates the fire is on a floor below
Smoke exiting under pressure with a Define neutral plane is a sign of a fire on the same structural level where the smoke is exit in
Fire exiting in opening most often a window with a Define neutral plane in the case that the opening is supporting a bi-directional flow of products of combustion away from the fire in oxygen toward the fire
Direct attack
Direct attack on the fire using a solid or straight stream uses water or foam most efficiently on fuel control fires
Indirect attack
An indirect attack on the fire using a straight or solid stream uses water most efficiently on ventilation control Fire’s the primary fuel within these types of fires are the fire gases that the combustion process inside a compartment produces
Gas Cooling
Is a way of reducing heat released from the hot gas layer this technique is effective when faced with a shielded fire
Transitional attack
The transitional attack is in a offencive tactic used in an offensive strategy that I see or initial company offers employees in which a hoseline is deployed from the exterior of the structure where smoke or Flames are visible to gain control of the fire prior to the deployment of interior hose line
Positive pressure attack
Positive pressure fans are most effective on Fire’s confined to a compartment the intent is to use high volume fans to create a slightly higher pressure in a Jason compartments enforce the products of combustion smoke today exterior of the structure through exhaust openings that already exists
Positive pressure attack considerations
The two main considerations for PPA fire location and exhaust to intake size ratio ratio is the comparison of the area of all exhaust openings compared with the surface area of all compartment intake openings
PPA is only in an effective tactic if the location of the fire is known in the appropriate exhaust to intake ratio greater than 1 can be achieved
AIR monitoring research
International Agency for research identified more than 30 carcinogens in fire smoke
The firefighter cancelled support strongly recommends firefighters used SCBA is from the beginning of the firefighting operations into the end of overhaul
Fire officer certified in NFPA 1021
Should be able to determine the cause and origin of most fires
Flow path
Is the volume between an inlet and in outlet that allows the movement of heat and smoke from the higher pressure within the fire area towards the lower pressure areas accessible via doors and window openings
Location and extent of the fire
The stage of the fire and whether it is fuel or ventilation control or a primary consideration in determining tactical ventilation procedures
Weather conditions
The most important weather-related influence on ventilation is when when conditions must always be considered when determining the proper means and location of tactical ventilation in all types of structures
Exposures
Firefighters must consider both internal and external exposures ventilation below the highest point of the building creates a danger that Rising Fire gases will ignite portions of the building above the exhaust point heat and fire gases may be drawn into open windows or attic vents above a ventilation opening and they may also ignite the eaves of the building or adjacent structure
High-rise fire search and rescue
The Personnel required for search and rescue and firefighting operations in high-rise buildings are often four to six times as great as required for a fire in a typical low rise building
Smoke movement
Three common types of movement are 1 floating or hanging 2 volume pushed 3 heat pushed
Test question
Floating or hanging lost its heat smokes the same temperature as the air around it this characteristic is often found in air-conditioned buildings fires that are sprinkler controlled or where smoke particles are filtered and cool by passing through cracks in walls
Test question
Occupant survival profile
Is a type of size up that should be employed to evaluate the potential of an occupant being alive within a structure fire environment I see ask:
1 are occupants suspected of or known to be trapped
To is it reasonable to assume that the occupants are still alive
Command options
First arriving officer have several options for command
1 investigation option nothing showing
2 fast attack or mobile command option
3 stationary comand incident command post option
If the incident is one in which there the direct involvement of the company officer will impact the outcome a mobile command should be utilized
Situations in which mobile command may be used
1 Life Safety situation such as a victim rescue
2 offensive fire attack switch are in the marginal mode
3 any incidents where the safety of firefighter is a major concern
4 incidents that require further investigation by the company
5 crew members need closer supervision due to being new and inexperienced
Factors for confinement of Fire
Facts needed
1 type of construction
2 type of fire protection system or lack of system
3 building occupancy type
4 contents within a compartment
5 flammability and combustibility of contents
6 distance between involved in uninvolved content
7 water supply vs demand fire flow
8 number of stories
9 barriers to fire spread
10 heating ventilation and air conditioning systems
11 current location and stage of Fire
12 resources immediately available
13 rescue or exposure tactics implemented
14 additional fuel or ignition sources
15 explosion potential internal and external
16 fire Behavior
17 closing fire doors
