Fire Investigator - Master For TCFP Test 2023

Is NFPA 921 a guide or a standard? - It is the Guide for Fire and Explosion Investigations What are the six steps of the scientific method? - Recognize the need Define the problem Collect the data Analyze the data Develop a hypothesis Test the hypothesis What step of the scientific method is inductive reasoning? - Analyze the data What step of the scientific method is deductive reasoning? - Test the hypothesis What are the four parts of the fire tetrahedron? - Fuel (reducing agent) Heat Oxidizing agent Uninhibited chemical chain reaction What kind of reaction absorbs energy, an endothermic or an exothermic reaction? - Endothermic What is heat transfer by direct contact called? - Conduction What is heat transfer by gas flow / air movement called? - Convection What is heat transfer by microwave energy called? - Radiation What is a fuel controlled fire? - A fire that is limited by the amount of combustibles. What is a ventilation controlled fire? - A fire that is limited by the amount of oxygen. What are the stages of fire growth? - Ignition Growth Flashover Fully Developed Decay What is a flashover? - The transition phase from growth to fully developed, where all surfaces reach ignition temperature almost simultaneously. What is ignition of the underside of the hot gas layer called? - Flameover or rollover What factors influence flashover conditions? - Size of the compartment Height of ceiling Ventilation Amount of fuel Layout of fuel Location of fire in the compartment What are fire patterns? - The physical manifestation of the affects of fire on materials. What are the different types of fire patterns on the walls and ceiling? - Plume Generated patterns (often V shaped) Ventilation generated patterns Hot gas layer patterns (Line of demarcation) What is spalling? - The separation of chunks of concrete with explosive force caused by the expansion of water (moisture) trapped in the concrete as it turns to steam What is char? - Pyrolized carbonaceous material What is oxidation? - Physical change in appearance of a material resulting from the combination of oxygen. What is alloying? - Mixing two metals heated then cooled to change their properties. Often melts at a lower temperature. What is a clean burn? - When there was enough heat to burn away all carbon deposits (soot) on a surface leaving a "clean" surface. Occurs on non-combustible surfaces. What is soot? - Elemental carbon produced during incomplete combustion. What is calcination? - When chemically bound water is driven out of gypsum walls by the heat of the fire. Does a 25 Watt light bulb expand towards the fire or pull inward away from it? - Bulbs 25 watts or less pull away. Bulbs greater than 25 watts will expand towards the fire. What causes heat shadowing? - An object blocking the travel of radiated heat. What is a dead load? - The weight of things attached to the building, like flooring, cloumns, and roof coverings. What is a live load? - A load that can move, like people, furniture, wind, water, and snow. What is compartmentation? - Design features of a building that limit fire growth to the room of origin. What are the five building construction types? - Type I - Fire resistant Type II - Non combustible Type III - Ordinary Type IV - Heavy timber Type V - Wood frame What is ordinary construction? - Exterior walls are masonry and frame is wood. What is wood frame construction? - Lightweight wood construction, used in apartments, houses. What is platform frame construction? - Each floor is a seperate platform. What is balloon frame construction? - The wall studs extend from the foundation to the roof. What is Ohm's Law? - V=IR (E = I x R) What is voltage? - Pressure What is current? - Flow What is resistance? - Friction, opposition to the flow What is an overload? - Power needs exceed the circuit's capacity. Alternating Current VS Direct Current - Alternating current - the electrons flow out from the source and then back to it, alternating directions. Direct current - electrons flow one way. Single Phase service - Residential. Three conductors: Two insulated conductors at 120 V each, and a bare ground wire. Three phase system - Commercial. Four conductors: Three insulated conductors (480, 240, or 208 V), and a bare ground wire. What is the difference between grounding and bonding? - Grounding connects the system to the earth (ground). Bonding connects to systems together so the charge stays the same between them. What is overcurrent protection? - A device that protects the system from excess current. Includes: Circuit breakers Plug fuses Type S fuses Time delay fuses Cartridge fuses What are the colors of residential wires? - Hot - black or red Neutral - gray or white Ground - bare or green What are some methods of electrical heat production? - Resistance heating Short circuit Ground fault Parting Arc Excessive current What is the difference between and arc and a spark? - Sparks are thrown metal particles Arcs are brief discharges of electricity What is arc tracking? - Arc following salts, dusts, or liquids along a path. What is arc mapping? - Mapping out of electrical damage in a circuit. What is static electricity? - A stationary charge caused by movement of one object against another. Lighting is a static disharge. What are the five conditions nessecery for Static Arc Ignition? - A Means of static generation A means of accumulating and maintaining the charge A static discharge with sufficient energy A fuel source Coexistence of the arc and fuel source Name two fuel gasses: - LP (liquid petroleum) Natural gas What is the difference between tanks and cylinders for LP gas? - Tanks: storage with greater than 1000 LBs water capacity. Cylinder: Portable, usually consumer. What are some human factors related to fire initiation in a structure? - Improper maintenance and operation