Step and Touch Potential Explained
Whether you’re a seasoned professional or new to the crew, knowing how electricity travels and understanding step and touch potential is crucial in keeping everyone on your jobsite safe when working near power lines.
There are three basic rules about how electricity travels:
- It takes the most efficient path to the ground — even if that means going through you
- It moves from higher to lower voltage areas
- Once it reaches the ground, electricity dissipates as it moves away from the source, like ripples on water, and creates different voltage areas
If you’re standing with one foot in a higher voltage area and one foot in a lower voltage area, the electricity will use your body as the most efficient path to travel to the lower voltage area. This is called step potential and occurs when you walk too close to energized ground, whether caused by an object or piece of equipment that has contacted a power line or even a downed line. Your best line of defense is to always stay at least 10 metres away from any live electrical source contacting the ground.
Touching an electrified object also puts you at risk of becoming a conduit for electricity to flow to the ground. This is touch potential. You can eliminate the risk of touch potential by staying away from electrified objects or if you’re already in the danger zone, carefully shuffling at least 10 metres away.
Stuck in a vehicle or piece of equipment that has contacted a line? The safest thing to do is stay where you are and only exit if it’s no longer safe to stay put (e.g. if the vehicle or equipment is on fire).
While these tips can help reduce the risk of an electrical shock after a power line contact has occurred, preventing the contact from happening at all is key. Before any work begins on your jobsite, contact your local utility provider and request a locate by contacting Alberta One-Call.
Still have questions? Check out our online power line safety tutorials and earn free swag for you and your crew.