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How to Avoid Electrical Hazard


Quiz Questions

1. According to page 7, the “freezing” current or “let-go” range for men is:
9-30 milliamperes
6-25 milliamperes
50-150 milliamperes
2. If a person is “frozen” to a live electrical contact, shut off the current immediately. If this is not possible, use boards, poles, or sticks made of wood or any other non-conducting materials and safely push or pull the person away from the contact.
True
False
3. Insulators such as glass, mica, rubber, or plastic used to coat metals and other conductors help stop or reduce the flow of electrical current. This helps prevent shock, fires, and short circuits. To be effective, the insulation must be suitable
for the voltage used and conditions such as temperature and other environmental factors like moisture, oil, gasoline, corrosive fumes, or other substances that could cause the insulator to fail.
True
False
4. "Grounding" a tool or electrical system means intentionally creating a low-resistance path that connects to the earth. This prevents the buildup of voltages that could cause an electrical accident.
True
False
5. Grounding is normally a secondary protective measure to protect against electric shock. It does not guarantee that you won’t get a shock or be injured or killed by an electrical current.
True
False
6. A service or system ground is designed primarily to protect machines, tools, and insulation against damage. One wire, called the "neutral" or "grounded" conductor,
is grounded. In an ordinary low-voltage circuit, the white or gray wire is grounded at the generator or transformer and at the building’s service entrance.
True
False
7. Which one of the following should be done as a safe work practice to avoid accidents
De-energizing electric equipment before inspection or repair
keeping electric tools properly maintained
exercising caution when working near energized lines
using appropriate protective equipment.
All of the above
8. Employees unqualified to work with electricity, as well as mechanical equipment, should remain at least 10 feet (3.05 meters) away from overhead power lines. If the voltage is more than 50,000 volts, the clearance increases by 4 inches (10 centimeters) for each additional 10,000 volts.
True
False
9. All employees should be trained to be thoroughly familiar with the safety procedures for their particular jobs. Moreover, good judgment and common sense are integral to preventing electrical accidents. When working on electrical equipment,
for example, some basic procedures to follow are to:

  • deenergize the equipment,
  • use lockout and tag procedures to ensure that the equipment remains deenergized,
  • use insulating protective equipment, and
  • maintain a safe distance from energized parts.
True
False
10. The first step before beginning any inspection or repair job is to turn the current off at the switch box and padlock the switch in the OFF position. This applies even on so-called low-voltage circuits.
True
False