Research Paper Example on Modern Fire and Legacy

The chemistry of fire is important for the firefighters. In understanding this chemistry oxidation and combustion, the latter can be defined as a chemical reaction between an oxidizer and fuel. The resulting reaction is often exothermic and may generate light. It is critical to understand modern fires and legacy fires. This paper will focus on combustion, oxidation and basic mechanisms of fire spread.

When oxidation is not combustion

Not all forms of oxidation of fuel may be considered as combustion. In a situation where oxidation occurs, and no heat is released, the process cannot be regarded as combustion. Whenever oxidation fails to occur at the molecular level, the process of combustion may not occur (Gann & Friedman, 2014). According to Hall (n.d), oxygen and fuel often interact in the same environment with minimal instances of oxidation likely to take place. However, the lack of adequate energy to break the chemical bond prevents the oxidation process from proceeding to combustion. The chemical bond can only be broken through an ignition process.

When combustion is not oxidation

Some instances of combustion may not involve the oxidation process. To understand this concept, it is paramount to establish the difference between flaming and non-flaming combustion. The non-flaming combustion does not involve the reaction between oxygen and fuel. Examples of such combustions include self-sustained combustion, oxidative pyrolysis and anaerobic pyrolysis (Gann & Friedman, 2014). The self-sustained combustion is a non-flaming combustion that includes types such as the smoldering combustion or glowing combustion. Oxidative pyrolysis is a non-flaming combustion that includes thermal radiation or conduction that has been externally applied. Anaerobic pyrolysis also referred to as oxidizer-free pyrolysis is also non-flaming combustion that includes thermal radiation or conduction that has been externally applied.

On the other hand, flaming combustion includes free burning in a well-ventilated area or unventilated area. The unventilated flaming combustion may include post-flashover flames. Flaming combustion results from a reaction between oxygen and fuel.

Basic mechanism of fire spread

It may be argued that the fire may spread due to two main reasons; the presence of fuel and presence of oxygen (Kerber, 2014). However, other factors such as relative humidity, temperature, and air currents may also affect the spread of fires (Hall, n.d). The knowledge of fire ventilation provides an opportunity for understanding how fire spreads. The presence of a flaming combustion can result to heat generation and flashovers. However, the flashover will depend on the percentage ventilation. Well ventilated rooms provide an opportunity for a fire to consume as much oxygen as possible which enhances the growth of the fire. After the fire reaches a point where it consumes all oxygen, there may be no chance for the fire to grow as this is limited ventilation situation.

It has also been explained that, once an ignition has occurred, the kinetic energy of molecules is increased which is capable of breaking existing bonds. New bonds are formed and the process produces heat. This heat continues to work as a catalyst for speeding up the chemical reaction thus making a fire self-sustaining. Therefore, reducing one of the elements in the combustion process may affect the spreading of the fire. For instance, cooling reduces the kinetic energy of fuel thus preventing the spreading of fire. Eliminating oxygen or fuel can also be considered as removing one of the reactants thus combustion may not occur.

References

Gann, R., & Friedman, R. (2014). Principles of Fire Behavior and Combustion. Massachusetts: Jones & Bartlett Publishers.

Hall, J. (n.d). A comparison of modern & legacy fires. Retrieved from http://www.belmontfiredepartment.com/files/Page_5_and_6_Jumpseat_Jargon.pdf

Kerber, S. (2014). Analysis of changing residential fire dynamics and its implications on firefighter operational timeframes. Retrieved from https://newscience.ul.com/wp-content/uploads/2014/04/Analysis_of_Changing_Residential_Fire_Dynamics_and_Its_Implications_on_Firefighter_Operational_Timeframes.pdf