Working Near Electrified Lines Flashcards

What is the term used for the voltage that can pass through the ground from a downed electrified rail or wire, creating a hazard over a wide area?

Answer: Step potential

Step potential is the voltage difference between two points on the ground surface, which can cause current to flow through a person's legs.

When working near a 750V DC electrified third rail, what is the minimum approach distance a worker must maintain without protective equipment?

Answer: 12 inches

A minimum approach distance of 12 inches is generally required from a 750V DC third rail without special protective equipment.

Which condition makes working near electrified lines MORE dangerous than usual?

Answer: Wet or humid conditions

Wet or humid conditions lower the resistance of materials and the human body, increasing the risk of electrical shock.

A train is approaching while a worker is within the electrified zone. What is the FIRST priority?

Answer: Move to a place of safety immediately

Personal safety is always the first priority — the worker must immediately move to a designated place of safety before the train arrives.

What does 'bonding' a section of track mean in the context of electrified railway work?

Answer: Electrically connecting components to equalize potential and reduce shock risk

Bonding equalizes electrical potential between conductive components, reducing the risk of dangerous voltage differences during work.

Who is responsible for issuing a 'Line Blockage' or electrical isolation before track workers enter an electrified work zone?

Answer: An authorized controller or electrical supervisor

Only an authorized controller or electrical supervisor has the authority to issue a line blockage or confirm electrical isolation.

What is 'induced voltage' and why is it a hazard near electrified lines?

Answer: Voltage generated in conductors near high-current lines without direct contact

Induced voltage is created electromagnetically in nearby conductors (like long tools or equipment) due to proximity to high-current electrified lines, posing a shock risk even without direct contact.