Fire Behavior- Introduction to Fire Suppression
Continuing Education Units (CEU): 0.10
Expected Duration: 1 Hour
This self-paced online course covers basic concepts about fire, with a focus on fire sprinkler and fire alarm systems. Fire is a very complex physical phenomenon. The effect that is called "burning" is the result of many physical and chemical interactions.
Upon completion you should be able to:
- Explain why fire is a process and define ignition
- Explain the relationship between lean and rich flammable vapors
- List the people who should be present at a fire pump acceptance test
- Explain the "fire triangle"
- Discuss the relationship between fire plumes and ceiling jets, and explain the importance of understanding each
- Define and explain key concepts, including British thermal unit (BTU), latent heat of vaporization, specific heat, exothermic reaction, endothermic reaction, physical fire separation, smothering, chemical modification, and dilution
- List and explain the three methods of heat transfer
- Explain how various substances function as fire suppression agents
- Explain the difference in high expansion and blanketing foams
Who Will Benefit
Anyone whose job involves designing, reviewing, evaluating or installing fire protection systems, including: designers, installers, engineers, electrical contractors, technicians, project managers, fire marshals, and architects.
- In order to understand the details of sprinkler protection, it is imperative that people working in the field have a basic understanding of some of the principles of fire science and behavior and how they affect suppression.
- Fire is a complex reaction that is based in chemistry and follows the laws of physics. Thermodynamics is a big part of fire spread. To be able to suppress or control a fire may well require the knowledge of fire chemistry and the understanding of some basic laws of physics. The most basic of these laws is that mass absorbs energy. This principle, coupled with the fact that fire burns on surfaces, explains why some objects burn so readily.
- Ignition can't take place unless the fuel is correct, the proper amount of air is present, and an energy source of sufficient size is available. Once these elements are in place, combustion begins, and a complex and ever-changing chemical chain reaction is sustained. To eliminate a fire requires the removal or reduction of one of the four elements. This can be done by cooling, smothering, or changing the chemical composition of the fire reaction. Different agents will affect one of these mechanisms to cause suppression.
- Fire is either exothermic (releases heat) or endothermic (absorbs heat). Heat from a fire is transferred through conduction, convection, or radiation, and many times in a fire, all three vehicles are being used at the same time.
- In a fire, heat rises in a buoyant energy wave known as a fire plume. The velocity is dependent on the fire growth, and when a horizontal barrier is in place, the plume of energy spreads out in all directions along the horizontal barrier to become a ceiling jet. The plume and jet carry the products of combustion to objects, such as fixtures on the ceiling, but also to sprinklers and detectors.
- Probably the most effective agent in suppression is steam. Steam is derived from the water spray absorbing heat and increases the ability of water to absorb additional heat through the effect of expansion, allowing additional surface area to impact the heat of the fire.