OSHA 30-Hour Construction Outreach (knowledge check)
Focus Four: electrocution: practice questions
Our OSHA 30 Construction bank has 18 questions on this topic. Here are 5 of them with answers; the full mock exam draws from every topic, like the real one.
Question 1
Under Table A, what clearance is required for a line over 200 kV up to 350 kV?
- 10 feet
- 15 feet
- 35 feet
- 20 feet
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D. 20 feet — Table A requires 20 feet for lines over 200 to 350 kV, 25 feet over 350 to 500 kV, and 35 feet over 500 to 750 kV.
Question 2
What must a dedicated spotter used for crane work near power lines do?
- Stay in continuous contact with the operator and watch the clearance
- Also act as signal person for the load and rig loads
- Stand under the boom to see better and also rig and signal the loads
- Operate the crane when the operator takes a break
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A. Stay in continuous contact with the operator and watch the clearance — A dedicated spotter must be in continuous contact with the operator, use a visual aid to judge the clearance, and be positioned to see the clearance; spotters must be trained.
Question 3
What is the alternative to GFCIs for ground-fault protection on construction sites?
- Using only two-prong cords
- An assured equipment grounding conductor program
- Wearing leather gloves and rubber boots whenever tools are plugged in
- Using longer extension cords
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B. An assured equipment grounding conductor program — Employers must use either GFCIs or an assured equipment grounding conductor program covering cord sets, receptacles and cord-and-plug equipment.
Question 4
Where must ladders have nonconductive side rails?
- On every job site, for every ladder longer than 20 feet, whether or not electricity is present
- Only on ladders longer than 20 feet
- Where the worker or ladder could contact exposed energized electrical equipment
- Only outdoors, or on ladders longer than 20 feet
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C. Where the worker or ladder could contact exposed energized electrical equipment — Ladders must have nonconductive siderails if used where the employee or ladder could contact exposed energized electrical equipment.
Question 5
How must temporary lights be hung?
- From their cords, tied to rebar or nails, as long as the cord is in good condition
- From nails driven through the cord
- From the nearest sprinkler pipe
- Not by their electric cords, unless designed for it
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D. Not by their electric cords, unless designed for it — Temporary lights must not be suspended by their electric cords unless the cords and lights are designed for that purpose, and lamps must be protected from contact or breakage.