NFPA 921 Chapter 9 Electricity and Fire Questions and Answers

NFPA 921 Chapter 9 Electricity and Fire Questions and Answers electrical equipment should be considered as an ignition source - ANSWER equally molten metal being deposited has same composition if the subject metal is ___________ melting - ANSWER extraneous kilopascals or psi are the two measurements of __________ pressure - ANSWER hydraulic is uncommon and in order to positively identify extraneous melting it generally requires - ANSWER microscopy and often sectional can be found on conductors, conduits, and on grounded surfaces or surfaces of different potential - ANSWER arc marks voltmeter records the _____________ between two points - ANSWER potential difference the unit measurement of potential difference - ANSWER volts the presence in a conduent is indication of arcing but the absence does not indicate the absence of arcing - ANSWER blow holes flows in a useful way in the electrical system - ANSWER charge the most frequently used method of examination of arcing involves running lightly glove hands along the length of the examination subject while using bright oblique lighting to visually observe - ANSWER shadows cast by the light source an accumulation of electrons just as water is an accumulation of water - ANSWER charge two methods of retention of the conductors - ANSWER wire ties or rolling them into a coil charge is measured in - ANSWER Coulombs non-damaging tools used for removal of insulation material with relatively little risk of copper damage - ANSWER nylon brushes and bamboo skewers means that the underground conductor side and the grounded side or sides are located to demonstrate the complete circuit related to the fault and the remaining arc marks - ANSWER both sides of the arc or the arc mark mate the rate of charge flow is called - ANSWER current although not always possible due to collapse and other damage to circuits the documentation should always include the _______________ upon which it was found - ANSWER circuit identification