Structure Fire 1 Flashcards
What is the fire triangle elements?
- Oxygen
- Fuel
- Heat
By manipulating the fire triangle firefighters can effectively control and extinguish fires
What are the 3 types of matter?
- Solids
- Liquids
- Gases
What is pyrolysis?
The breakdown of a substance caused by heat
What is latent heat of vapour?
The amount of heat needed to change a substance from liquid to vapour (eg. water to stream)
What is heat release rate?
The amount of heat energy released over time
What is flash point?
The lowest temperature a substance produces a flammable vapour. The flame is not sustained and it flickers
What is fire point?
The lowest temperature a substance produces vapour that can be sustained
What is auto ignition temperature?
The temperature a fuel will ignite on its own.
What is the flammability range?
The ratio of fuel to air. Identification of the lower and upper limits that fire or explosion can occur if a flame or spark was present.
What is the neutral plane
The line between hot fire gasses (smoke) and fresh air..
What is gravity current?
When fresh air is denser than the hot gases existing in the room
What is Thornton rule?
The more oxygen you add the bigger and hotter the fire will get. 1kg of oxygen = 13.1mj of energy
What is Charles law?
Gases expand when heated
Gases become less dense and will rise when heated
What is gay-lussacs law?
When gases are heated in a confined space the pressure will increase
What is fuel controlled?
A fire with more than enough oxygen for combustion
What is ventilation control?
Fire is limited by the available air supply
What is the basic fire progression?
- Developing fire
- Flashover
- Fully developed
- Decay
What are signs of flashover?
- Ventilation controlled, vented fire
- Painful radiant heat
- Low turbulence neutral plane
- Fingers of flames through smoke
- Hot surfaces
- Increased rate of pyrolysis
- Increased turbulence of the natural plane
What are the signs of backdraught?
- Ventilation controller, non vented fire with
- Lack of visible flames
- Dirty smoke
- Smoke pulsating through gaps
- Air being drawn in
- Indicators of extreme heat
Fuel controlled vs ventilation controlled?
Fuel controlled
- developing flame
- high neutral plane
- better visability
-bright yellow flame
Ventilation controlled
- fully developed fire
- low neautral plane
-poor visability
-air being drawn back to fire
What is the purpose of a direct attack?
To put the fire out using a jet or spray
What is exterior application?
Putting water on the external to help interior operations
What is an indirect attack?
To put out the fire by creating large amounts of steam
What is gas cooling?
Used to control the fire environment while fire fighters advance forward
What are the methods of heat transfer?
- Conduction- through things
- Convection- circular
- Radiation - direct heat from the fire source
What are the different classes of fire extinguishers?
Class A- wood, paper cloth, plastics
Class B - liquids petrol, oil, paints
Class C- gasses, LPG, natural gases
Class D- metals, aluminium
Class E- electrical
Class F- oils and fats
What are the different extinguishers and what classes can you use them for?
- Red - water extinguisher (class A)
- blue - foam Extinguisher (class B- liquids)
- white dry chemical - (class C, gases)
Black - co2 - class F electrical
Oil/yellow- wet chemical - cooking fats
What is salvage?
Describes the actions taken to minimise damage caused by Fire and Water. This also help with fire investigation
What is overhauling?
Is the necessary job of checking, turning over and wetting down materials
Signs of potential collapse?
-columns buckling
- floors damage
- displaced columns
-bulging walls
-cracks in walls
-dropped arches
What is the value of overhauling?
-Locate hidden fires
- prevent rekindling
-help determine cause of fire
-help with preserving evidence
-prevent unnecessary damage
What are the 3 stages of salvage?
- Preventative
- Protective
- Recovery
What are the 2 ventilation types?
Natural
Mechanical
What is fire?
The combustion of fuel and oxygen causing heat and light.
What is flashover?
When the heat builds up in a room to the point that all the vapours and fuel ignites simultaneously…
