Arc Flash 101

Posted on September 27th, 2021
Posted in Uncategorized   

Have you ever been on site where personnel open energized electrical equipment, and wondered if it is safe? Best practice is for electrical equipment to only be accessed when the power is shutoff, and the equipment is verified to be completely deenergized. A loose connection, a dropped screwdriver or a scared animal that made the gear it’s home could cause a fault condition that could release massive amounts of energy that can injure or kill people nearby. In some circumstances, shutting power off is not practical, but there are ways to protect personnel. Beyond lock-out/tag-out procedures, arc flash analysis and labeling disclose how much potential energy is available, and guides personnel to wearing adequate personal protective equipment to protect themselves from dangers hiding behind a closed door.

Electrical engineers can collect field data or utilize information from an initial design to create models that simulate what could happen if a worst-case fault were to occur inside energized electrical equipment. They can then take that data and create equipment-specific labels that are placed on the equipment to inform personnel as to the potential energy risks and provide awareness of how much potential energy could be released by opening that energized electrical equipment.

Arc flash labeling is first and foremost about keeping people safe, which is why arc flash modeling studies and labels are mandated by OSHA. Many operators’ insurance carriers also require these studies, since field accidents can be extremely costly, not only due to personnel injuries, but these energy releases can also damage equipment, rendering it unusable and causing costly downtimes.

The best time to do this study is during initial engineering, since the design process can be optimized to help reduce potential energy through specific equipment selection or creating safety focused breaker settings. If an arc flash study doesn’t occur during the design phase, the arc flash modeling and data analysis can be performed paired with field investigations to address problem areas and determine if there are any steps that can be done to reduce potential dangers down to manageable levels.

At Halker, our engineers have the experience to perform studies on a variety of electrical systems and assist clients with making their operations and facilities safer, whether it is updating existing models, performing field walkdowns and doing the studies from scratch, or starting your design off on the right foot with proper equipment studies and specifications.

For more on the requirements, codes, and standards that guide this process, see the Halker information sheet at the link below:

View PDF: Arc Flash Information Sheet