When working around electrical utility lines or transmission equipment, there is a risk that it will become reenergized. To combat this risk, OSHA requires that an equipotential zone (EPZ) be created at worksites where differences in electric potential are a possibility. To do this, a temporary grounding solution, such as EPZ grounding mats, must be identified and implemented.

What Are EPZ Grounding Mats?

EPZ grounding mats are one-piece galvanized steel grates that create an equipotential bonded and grounded work zone. This approach is a more reliable option for EPZ safety than a ground chain, chain-link fencing, or other alternative methods for grounding. When workers stand on EPZ mats, the near-identical state of electrical potential between any two points on the body protects them from electric shock.

EPZ grounding mats bond all conductive components to an earthen ground to create a predominant circuit. The voltage gained from the circuit is transferred to EPZ grates, where the electrical potential of conductive equipment is equalized.


What Are the Benefits of Using EPZ Mats?

In addition to creating a safer work environment, EPZ mats come with other notable benefits.

Get protection from step-potential and Grade 5 fault currents.

The most important benefit of EPZ mats is providing a safe work area. Without an effective equipotential zone, workers risk exposure to lethal levels of electricity. Using EPZ mats makes it safer for people to walk in places with dangerous levels of electricity.

Get bonding and grounding in a single system.

Equipotential grounding requires:

  • Low-impedance grounding to limit voltage rise
  • Bonding to eliminate differences in potential.

EPZ mats combine both of these elements into a single system for efficient installation.

Quickly install and remove mats.

EPZ mats can be easily transported in fewer deliveries and assembled more quickly than other types of solutions. This saves on labor costs to install and remove an equipotential zone.

Create a strong and stable work platform.

In addition to protecting workers from hazardous step-potential and faults, EPZ mats create a stable foundation and continuous work surface over soft or uneven terrain. This allows heavy equipment to be safely moved around the site. The secure links between mats ensure that they don’t shift or move as materials and equipment are moved around. Using an EPZ mat system with walk-off areas also reduces trip hazards at the site.

Reduce your environmental footprint.

Temporary EPZ mats leave no trace at the worksite and help protect the ground below from the sustained impact of foot and vehicle traffic. When reusing mats at multiple sites, thorough cleaning of the impervious steel ensures that no contaminants or invasive species are transferred between sites. In combination with timber mats to provide safe access to more remote sites, EPZ mats contribute to low-impact power line construction, even in protected areas.


When to Use EPZ Mats

EPZ mats are most commonly used at worksites for power line construction projects. This could include projects related to:

  • Transmission lines
  • Distribution systems
  • Substations
  • Renewable energy

EPZ mats should be considered for any project that requires an equipotential zone to protect ground crews.


Start Using SAFESTEP™ EPZ Grounding Grates

YAK MAT’s SAFESTEP EPZ Grounding Grates can be quickly and easily connected to make work areas of any size at high-voltage sites. These performance-tested mats are available in multiple sizes so they can be configured to accommodate sites across a variety of terrain and dimensions. Made from resilient materials, EPZ mats can be reused on multiple job sites without impacting quality or efficacy. 

Learn more by downloading the SAFESTEP EPZ Solutions Package, which includes an EPZ Safety Checklist, EPZ Lab Testing Report, and Worker Protection Video.

Download the Package