CFEI Definitions (Definitions from NFPA 921 and NFPA 1033) 2024

CFEI Definitions (Definitions from NFPA 921 and NFPA 1033) 2022 Absolute Temperature. - Answer ️️ -A temperature measured in Kelvins (K) or Rankines (R). Accelerant. - Answer ️️ -A fuel or oxidizer, often an ignitible liquid, intentionally used to initiate a fire or increase the rate of growth or spread of fire. Accident. - Answer ️️ -An unplanned event that interrupts an activity and sometimes causes injury or damage or a chance occurrence arising from unknown causes; an unexpected happening due to carelessness, ignorance, and the like. Ambient. - Answer ️️ -Someone's or something's surroundings, especially as they pertain to the local environment; for example, ambient air and ambient temperature. Ampacity. - Answer ️️ -The maximum current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. [70, Article 100] Ampere. - Answer ️️ -The unit of electric current that is equivalent to a flow of one coulomb per second; one coulomb is defined as 6.24 × 1018 electrons. Arc. - Answer ️️ -A high-temperature luminous electric discharge across a gap or through a medium such as charred insulation. Arc Mapping. - Answer ️️ -The systematic evaluation of the electrical circuit configuration, spatial relationship of the circuit components, and identification of electrical arc sites to assist in the identification of the area of origin and analysis of the fire's spread. Arc Site. - Answer ️️ -The location on a conductor with localized damage that resulted from an electrical arc. Arcing Through Char. - Answer ️️ -Arcing associated with a matrix of charred material (e.g., charred conductor insulation) that acts as a semiconductive medium. Area of Origin. - Answer ️️ -A structure, part of a structure, or general geographic location within a fire scene, in which the "point of origin" of a fire or explosion is reasonably believed to be located. (See also 3.3.132, Point of Origin.) Arrow Pattern. - Answer ️️ -A fire pattern displayed on the cross-section of a burned wooden structural member. Arson. - Answer ️️ -The crime of maliciously and intentionally, or recklessly, starting a fire or causing an explosion. Autoignition. - Answer ️️ -Initiation of combustion by heat but without a spark or flame. Autoignition Temperature. - Answer ️️ -The lowest temperature at which a combustible material ignites in air without a spark or flame. Backdraft. - Answer ️️ -A deflagration resulting from the sudden introduction of air into a confined space containing oxygen-deficient products of incomplete combustion. Bead. - Answer ️️ -A rounded globule of re-solidified metal at the end of the remains of an electrical conductor that was caused by arcing and is characterized by a sharp line of demarcation between the melted and unmelted conductor surfaces. Blast Pressure Front. - Answer ️️ -The expanding leading edge of an explosion reaction that separates a major difference in pressure between normal ambient pressure ahead of the front and potentially damaging high pressure at and behind the front. BLEVE. - Answer ️️ -Boiling liquid expanding vapor explosion. Bonding. - Answer ️️ -The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed. British Thermal Unit (Btu). - Answer ️️ -The quantity of heat required to raise the temperature of one pound of water 1°F at the pressure of 1 atmosphere and temperature of 60°F; a British thermal unit is equal to 1055 joules, 1.055 kilojoules, and 252.15 calories. Burning Rate. - Answer ️️ -See 3.3.99, Heat Release Rate (HRR). Calcination of Gypsum. - Answer ️️ -A fire effect realized in gypsum products, including wallboard, as a result of exposure to heat that drives off free and chemically bound water. Calorie. - Answer ️️ -The amount of heat necessary to raise 1 gram of water 1°C at the pressure of 1 atmosphere and temperature of 15°C; a