Arc Flash Hazard Prevention for Substations

Learn how to prevent this risky electrical hazard on your substation grounds.

What is arc flash?

When a fault arcs, the result is a rapid release of energy, causing what is called an arc flash. This usually occurs between phase bus bars larger than 120V. An arc flash is known to lead to explosions due to the highly conductive nature of the materials it is in contact with and the amount of energy it discharges during the flash. Arc flash is characterized by fiery explosions and deadly shrapnel.

How to avoid arc flash

The best way to prevent arc flash is to run your substation in compliance with OSHA standards. According to Substation Safety’s 6-point plan for arc flash OSHA compliance, you must at least provide an in-depth safety program to your employees, have an accurate analysis of the degree of arc flash hazard present on your substation, and provide training and equipment suitable for the hazard present. Visit OSHA’s website for more information regarding arc flash safety precautions.

Arc flash hazard analysis

Arc flash hazard analysis procedures are performed by a safety auditor. According to a list compiled by Substation Safety, the auditor collects the following data regarding the power distribution of a facility:

  • A one-line drawing of all components with nameplate specifications of every device
  • Details of the lengths and cross-section area of all cables
  • Utility information including the minimum and maximum fault currents that can be expected at the facility entrance

After this data has been collected, both a short circuit analysis and coordination study are performed. All resulting data is then filtered and compiled to create a facility-specific arc flash margin.

By educating your employees and providing the proper training and equipment, your facility will be well on its way to arc flash prevention and safety.