Basic Fire Dynamics Chapter 1 Flashcards
Fire dynamics
What are the two modes of combustion? 2.3
Non-flaming combustion
Flaming combustion
PS combustion can occur without fire.
Fire dynamics.
Non-flaming combustion occurs——- and at a—- temperature producing a —— glow in the material surface without flames. 2.3.1.
Which fire model best illustrates the elements required for non-flaming combustion?
2.4.1
More slowly
Lower temperature
Smoldering glow
Fire Triangle
Fire dynamics.
Flaming combustion is commonly referred to as fire because it produces a ——— the material surface. 2.3.2.
Visible flame ABOVE
Fire dynamics.
What are the names of the two models that are used to explain the elements of fire and how fire can be extinguish. 2.4.
Fire triangle
Fire Tetrahedron
Fire dynamics.
What would be examples of non-flaming combustion? 2.4.1.
Burning charcoal briquettes,
smoldering wood
fabric
What three almonds make up the Fire triangle?
2.4
Heat
Fuel
Oxygen
Which fire model best illustrates the elements required for non-flaming combustion? 2.4.1.
Fire triangle
Fire dynamics.
Fire tetrahedron was created to explain ——- combustion. 2.4.2.
Flaming
Fire dynamics.
Fire Tetrahedron, ( flaming Combustion) what are the four elements needed?
2.4.2
Fuel
Oxygen
Heat
Uninhibited chemical chain reaction.
Fire dynamics. Fuel.
Fuel may be found in three states of matter solid, liquid or gas.
Which one Burns?
2.5.1.
Only gases burn
Fire dynamics. Fuel.
Solids are converted into gas by —-?
Liquids are converted to gas by —-?
2.5.1
Solids- Pyrolysis
Liquids- Vaporization
Pyrolysis (decomposition of solids) often precedes ———-?
2.5.2
Combustion
Pyrolysis.
—— to ——- Ratio
Significantly affects the ease of ignition of solid fuels.
2.5.2
Surface to Mass Ratio
Fire dynamics.
What will ignite significantly quicker sawdust or a log?
2.5.3
Sawdust
It has increased surface to mass ratio thus more the material is exposed to heat and generates more burnable gases.
Fire dynamics.
Liquids are converted into gas by?
2.5.4
Vaporization
Fire dynamics
——— to ——— significantly affects the ease of ignition of ——— fuels.
2.5.4
Surface the Volume Ratio
Liquid fuels
PS The greater the surface area compared to volume faster the liquid will vaporize.
Fired dynamics.
Surface to Mass ratio ease ignition of ——-
Surface to Volume ratio ease ignition
of ———.
2.5.3
2.5.4
Solid (SMS)
Liquid (SVL)
Fire dynamics.
——— fuels can be the most dangerous because they already in the natural state required for ignition. No pyrolysis or vaporization will be needed to ready the fuel. 2.5.5.
Gaseous
Fire dynamics. Which fuels are the most difficult to contain?
2.5.5
Gaseous.
Fire dynamics.
When oxygen concentration is higher than —— materials exhibit very different burning characteristics.
Materials that burn at ——- oxygen levels were burn more intensely in oxygen enriched atmospheres. 2.6.3.
20.8%
Normal
Fire dynamics. Which law specifies that heat ALWAYS flows from hot substance to cold substance? 2.7.1.
Law of Heat Flow
Fire dynamics. Heat can travel throughout the building by three methods, which are?
2.7.2.
Conduction
Convection
Radiation
Fire dynamics. Which definition is this? Heat may be conducted from one body to another by direct contact of two objects or by intervening heat conducted medium material. Example of fireman crawling on the floor burns his knees.
2.7.3
Conduction
Fire dynamics, which definition is this? Transfer of heat by the movement of air or liquid. When water is heated in a container and expands and grows lighter hence the upward movement. 2.7.4.
Convection
Fired dynamics.
Which type of heat transfer can exponentially increase by wind. 2.7.4.
Forced Convection.
Fire dynamics
What is a critical factor in
Wind-Driven fires. 2.7.4.
Forced Convection
Fire dynamics.
——— describes heat transferred through the moment of heat waves. 2.7.5.
Radiation
T/F
Heat and light waves will cause convection heat to travel through a space until it reaches an object
2.7.5
False
Radiation
Fire dynamics.
What type of heat is one of the major sources of fire spread to exposures. 2.7.5.
Radiated
Fire dynamics.
What type of heat is also one of the major causes of firefighter burn injuries and flashovers.
2.7.5.
Radiated heat
Fire dynamics.
What is the preferred way to extinguish a smoldering fire. 3.5
Cooling
Fire dynamics
T/F
Combustion often proceeds pyrolysis.
5.2
False
Pyrolysis often precedes combustion.
Fire dynamics.
The lowest temperature of a liquid at which the liquid gives off sufficient vapors to ignite but will not continue to burn is known as? 6.2.
Flash Point
Fire dynamics.
A flammable liquid is a liquid that has a flashpoint below ?
6.2.1
6.2.2
Below 100’F
PS Combustible Liquid flashpoint equal to or greater than 100’F
Flashpoint Flammable Liquid?
6.2.1
Flashpoint Combustible Liquid?
6.2.2
Below 100’
Equal to or Greater than 100’
Fire dynamics
——— is the lowest temperature at which a liquid will ignite and achieve sustained burning.
6.3
Flashpoint
Fire dynamics
——— is ability of liquid or solid fuel to vaporize. 6.4.
Vapor pressure
What is the explosive range for natural gas? What is the LEL and UEL?
5% LEL to 15% UEL
