CFEI Study Guide Graded A+ 2024

CFEI Study Guide Graded A+ 2024 Evidence - Demonstrative Evidence - Documentary reports, etc... Evidence - Testimonial Evidence - illustrative Tangible items; see, touch, smell, hear. Written form; business records, banking, calendars, phone records, fire Competent live witness speaking under oath; two types; fact and expert Photos, sketches, maps, diagrams. Modes are frequently used at trial. Evidence - illustravtive Evidence collection & tag) Evidence - collection refuels. Heat transfer Photos and Videos; what, why, how, when Document in place, document the collection, use proper container, (flag, bag, Fuel gas powered tools outside the perimeter. Find out where tools were Conduction, convection, radiation Interviews Vehicle Fires Vehicle Fires Purpose of the interview; prepare for the interview, document the interview Sparks from an aluminum wheel are not a competent ignition source. The most common source of an open flame in a vehicle is an exhaust system backfire out of a carburetor. Vehicle Fires Vehicle Fires Carburetor backfire leaves a distinct pattern on the hood. Two basic fuel systems: vacuum/low pressure carbureted system, and high-pressure, fuel injected system. Vehicle Fires Loose battery connections; not over-current protected; loose connections can result in intermittent arcing. Vehicle Fires Vehicle Fires Vehicle Fires Explosions Power steering fluid: Flashpoint 347-356*F, autoignition 680-720*F. Automatic Transmission Fluid: Flashpoint 302-536*F, autoignition 626-716*F. Overcharging a battery does not cause it to explode. Low order damage: characterized by walls bulge out or laid down, virtually intact, next to the structure. roofs slightly left. Explosions Explosions f ire. Explosions Explosions High order damage: shattering of the structure, producing small debris pieces. Post blast effects: burned debris away-fire preceded, unburned the debris away-no Dust explosions: most often occur in confined areas of relatively wide dispersal. Search 1.5 times further than the farthest piece of debris. Fire effects/ fire patterns Char shrinks as it forms. More reliable for evaluating fire spread, deduce the direction based on depth, large shiny blisters (alligatoring) is not evidence of the use of an accelerant. Fire effects/fire patterns Spalling: loss of surface material due to cracking, breaking, chipping, breakdown in surface tensile strength, moisture present in the concrete, may appear lighter in color. Fire effects/fire patterns Fire effects/fire patterns Crazed glass: caused by rapid cooling. Light bulbs 25W or more "pull" (gases expand and bubble out); 25W or less contain a vacuum and can pull in. Fire effects/fire patterns duration, and intensity. Fire effects/fire patterns Annealing (softening) of springs may provide clues concerning direction, Saddle burns - A U-shaped burn pattern found on the top of floor joists, caused by fire burning down through the floor. Often, a saddle burn is caused by a burning liquid on the floor or radiant heat from a material close to the floor. Saddle burns display deep charring. Fire effects/fire patterns Inverted cone burns are indicative of the vertical flame plume not reaching the ceiling, short-lived fires with a low HRR Fire effects/fire patterns Heat Sources Melting Temperatures: Copper 1981*F; Aluminum 1220*F; Steel 2760*F Mechanical: converted to heat when two materials rub against each other and create friction. Chemical: chemical reaction; exothermic and endothermic. Electrical: Converted to heat energy; flowing through a conductor. Nuclear: splitting the nucleus of an atom into two smaller nuclei (nuclear fission) Electrical Resistance Heating: properly installed, produces low resistance. Loose connections: high resistance with increased heating at the contact. Electrical Ground Fault: the purpose if grounding an electrical system is to make sure that any housings or exposed metal in the system or connected to it cannot become electrically charged. Electrical Sleeving: the softening and sagging of thermoplastic conductor insulation due to the heating of the conductor. Electrical Lightning: a form of static electricity, a polarized electrostatic charge in the clouds