It goes without saying that hanging electrical lines is dangerous work. Given the lethal amount of voltage in play, mitigating the risk for workers is the highest priority. In fact, 8.5% of all construction-related fatalities in 2018 were electrocution-related.
Although much of the focus tends to be on protecting those crew members who are elevated, those on the ground shouldn’t be ignored. When it comes to keeping them safe, an equipotential grounding system is typically the most effective method. Understanding what these are and how they work is critical for any contractor who has to operate around high-voltage infrastructure or equipment.
Understanding the Danger
Appreciating the risk begins with knowing what electricity “wants.” Without getting too technical, electrical charges want to be equal. That means, when there’s a discrepancy in potential between two objects that touch each other, current will flow through them as the electricity seeks to equalize. If a person accidentally comes in contact with power lines, the electricity could travel through him or her unless he or she is grounded.
Grounding means giving the current a way to return to the ground safely in the event of a fault. Because the voltage of the ground is effectively zero, there will always be a difference in potential and the current will flow into the earth as long as it has a pathway to take it there.
What Is Equipotential Grounding?
When it comes to equipotential grounding zones, or EPZ grounding, the definition is relatively simple. An equipotential zone is an area in which the electrical potential between any two points on a worker’s body is effectively identical. This means he or she is protected from shocks caused by faults or lighting strikes because the work area is grounded. This directs any current along the ground instead of through workers’ bodies.
How Is an Equipotential Zone Created?
The earliest methods of grounding work sites were little more than improvisations. In many cases, a small chain was attached to conductors that extended to the earth. However, in 1994, OSHA began enforcing rules about protecting workers from sudden re-energization caused by faults. This meant crews had to become more cognizant about how they were facilitating a safe working environment. For linemen working on poles, this means connecting clamps to the lines with safety wires leading to a grounding bar. At ground level, however, there is more real estate to cover.
Many contractors turn to jury-rigged solutions such as laying chain-link fencing or hog-panel wire in order to create a ground for a wide area. However, these options don’t offer as much protection as crews may believe. That’s because these commonly found materials often aren’t manufactured to safely conduct fault current. There could still be a chance that anyone standing on the ground could become electrocuted.
Another disadvantage of these improvised methods is that they usually aren’t sturdy enough to stand up to constant foot and equipment traffic. This leads to breaks and shifting that reduce their effectiveness even further. That’s not to mention that it can create a tripping hazard for employees.
Finding a Better Solution
Creating an equipotential zone for electrical installation is a critical step crews can take for safety. Rather than trusting in methods that have a less-than-stellar success rate, site managers are recognizing the value of grounding grate systems. These are all-in-one galvanized steel grates that can be placed to create zones where the electrical potential is equalized. Because they are extremely durable and can be locked for stability, they offer a more complete solution. When faults occur and there is an accidental exposure to electrical current, these grates direct it away from people and equipment.
Turn to YAK MAT
YAK MAT’s EPZ Grounding Grate products can be deployed virtually anywhere high-voltage jobs are being conducted. This includes substations, renewable energy sites and areas where lines are being installed. They have been performance-tested for a range of short-circuit capacity tests and current withstanding scenarios. Available in 4-foot-by-3-foot and 8-foot-by-14-foot sizes, they can be configured to cover ground areas of practically any size, no matter what type of terrain they feature.
Because they are manufactured of highly resilient materials, they can be used on multiple job sites without any reduction in their quality or efficacy. To learn more about these products and how they can be used to ensure a safer job site, click here.