OSHA Electrical Hazards & Power Line Safety 3

Question 1

What must occur before anyone on the ground approaches or touches a crane that has made contact with an energized overhead power line?

Accepted Answer

The utility company must deenergize and confirm the line is safe

Answer

The crane operator must exit the cab first

Answer

A site safety officer must give verbal clearance

Answer

The crane load must be set down first

Question 2

What is 'step potential' in the context of crane electrical safety?

Accepted Answer

The voltage difference between two ground points that can drive current through a person's body from foot to foot

Answer

The voltage rating of the crane's control system

Answer

The potential energy stored in a raised load

Answer

The step-down voltage from transmission to distribution lines

Question 3

The minimum approach distances listed in OSHA's power line safety tables are determined primarily by which factor?

Accepted Answer

The voltage level of the power line

Answer

The weight of the load being lifted

Answer

The height of the crane boom above ground

Answer

The length of the rigging assembly

Question 4

What does OSHA 1926.1408 require when power line voltage information cannot be obtained before crane operations?

Accepted Answer

Maintain at least 20 feet of clearance from the lines

Answer

Assume 50 kV and use the 10-foot clearance rule

Answer

Suspend all operations until voltage is confirmed by the utility

Answer

Require a licensed electrician on-site during lifts

Question 5

Which practice best protects a crane operator from 'touch potential' hazards if the crane contacts an energized power line?

Accepted Answer

Remaining inside the cab without touching external metal surfaces

Answer

Wearing rubber-soled work boots

Answer

Grounding the crane outriggers with copper cables

Answer

Using fiber rope slings to isolate the load

Question 6

Under OSHA 1926.1408, what assessment must be completed before lifting operations begin in any work zone containing overhead power lines?

Accepted Answer

A determination must be made whether any part of equipment or load could enter the minimum approach distance during operations

Answer

A licensed engineer must sign a rigging plan

Answer

The operator must hold a current medical clearance certificate

Answer

Insurance documentation must be submitted to the project owner

Question 7

If an operator must evacuate a crane that is in contact with an energized power line, what technique minimizes the risk from step potential?

Accepted Answer

Jump clear of the crane with feet together, then shuffle or hop away in small steps

Answer

Step down carefully using the access ladder and walk away quickly

Answer

Lower the boom to the ground to create a ground path before exiting

Answer

Call for a fiberglass ladder to be brought to the cab door