In North Carolina, a local electric company sent a request for a replacement of a high voltage distribution switch for an underground system with another switch that included a disconnect on the load side.   The existing switch had only been in service for one year, but a new switch was needed, stemming from rapid growth of the area.  The new switch would allow the isolation of circuits on the load side independently of each other.

Shortly before 9:00am on a crisp spring morning, two electricians showed up to make the switch.  When they arrived, no one from the electric company was present.  They discussed whether or not the distribution switch was de-energized.  They opened the door of one of the cabinets, and one of the men started guiding a tic tracer.  He allowed it to make contact with a 23,000 volt source, sending 13,200 volts through the ground and into his body.  Paramedics arrived quickly on the scene, but he was pronounced dead at 10:20am.  The other worker received minor flash burns of the eyes and face and stated that he was “electrified,” shaken, and proceeded to run.

When the investigation of the incident was performed, it was determined the man who did not survive was not wearing the required personal protective equipment.  The system was not de-energized or properly grounded.  Written company work procedures require both of these factors.  To add to the tragedy, both workers were present at a safety demonstration that discussed the exact job being performed only two days prior to this incident.  Laws can be written and procedures outlined, but it is up to every individual to follow the rules and guidelines.  Personal protective equipment is designed to prevent accidents like this from happening.  It will do no good if it is not worn when needed.

A new law regarding arc flash, established by the NESC states, “Effective as of January 1, 2009, the employer shall ensure that an assessment is performed to determine potential exposure to an electric arc for employees who work on or near energized parts or equipment.  If the assessment determines a potential employee exposure greater than 2 cal/cm2 exists, the employer shall require employees to wear clothing or a clothing system that has an effective arc rating not less than the anticipated level of arc energy.”

This law will require workers to wear arc flash suits when exposed to an exposure greater than 2 cal/cm2.  Arc flash is the result of a rapid release of energy due to an arcing short circuit between two or more adjacent conductors.  The cause of the short normally burns away during the initial flash, and the arc fault is then sustained by the establishment of a highly conductive plasma.  Arc flash produces temperatures above 35,000 degrees and statistics say 2000 people are admitted to the hospital every year because of arc flash injury.  The risk of arc flash has contributed to new laws such as the one stated previously beginning in 2009.  It is imperative to protect yourself from the dangers of arc flash by wearing the proper personal protective equipment when working anywhere a potential exists for arc flash.