Ch 21 Electrical Fires and Emergencies Flashcards
(46 cards)
What we has what? Pg 523
Pressure, friction loss, and flow rate
Electricity has what? Pg 523
Pressure, known as electromotive force or electrical potential difference, and is measured in volts.
What is friction loss? Pg 523
Which is a measure of the resistance that it meets, is measured in ohms.
The flow rate in water is referred to what? Pg 523
In terms of gallons per minute, with electricity, it is called amperes (commonly referred to as amps for short).
Amperage is what? Pg 523
Is determined by the amount of voltage the conductor is delivering and the resistance that the wire or object in the path of the current is offering.
It takes far less than how many amp passing through your body to kill you? Pg 524
1
What is voltage? Pg 524
Can be described as the pressure that forces electrical current through the lines that carry it.
Many utilities refer to anything less than how many volts as low voltage? Pg 524
600
Resistance can be thought of in terms of what? Pg 524
Resistance to flow offered to the electricity.
A open circuit is what? Pg 524
Is an electrical circuit that does not permit electricity to flow because there is a break in the circuit wire or an open switch
What is a short circuit? Pg 524
When an electrical circuits normal path has been interrupted, current is permitted to flow through a path it was not intended to.
What is a utility ground? Pg 524
The wiring installed by the utility companies that permits electricity to flow back into their system and then into the earth or ground
What is a house ground? Pg 524
The wiring installed by the electrician when building a house that also permits electricity to flow back into the earth or ground in the event the utility ground is broken or open.
The black wire is called what? Pg 525
Hot wire
The white wire is called what? Pg 525
Neutral
There are two main hazards from electricity? Pg 527
Electrocution and burns
Alternating current flow hazardous to humans? Pg 527
• 1-5 mA: tingling sensation
• 5-10mA: pain
• 15 mA: Level where muscle construction prevents letting go of a wire in the hand.
• >50 mA: Loss of muscle control, cessation of heart and respiratory functions, death
All ladders and other equipment must be kept at least how many feet from overhead power lines? Pg 528
10 ft
What is voltage gradient? Pg 529
Is the result of current being dissipated to ground as it travels from a source. Such as downed high voltage wire.
Transmission line voltage carry likely exceeds how many volts? Pg 530
8,000 volts
Distribution line voltage carry between how many volts? Pg 530
601 and 8,000 volts
Initial responders should isolate the area at least what distance away from any break? Pg 538
At least one full wire span.
Keep at least how many feet away when using a fog nozzle from all electrical equipment when operating any handling? Pg 538
25 ft
Keep at least how many feet away when using a solid tip nozzle from any electrical equipment when operating handline? Pg 538
40 ft
