If you run an operation or are in charge of maintenance at a facility in which employees must work around electricity or energized electrical equipment, you need to make sure they are protected against any and all arc flash hazards.
An arc flash occurs when electricity jumps through the air between surfaces. When this happens, a huge release of electrical energy causes an explosive fireball. There is usually a log of flying shrapnel, a tremendous amount of heat and a very loud noise.
The occurrence of an arc flash can be unpredictable, but there is always the possibility of it when someone is working around energized equipment. While in the vast majority of cases any repairs to electrical equipment can be made while it is de-energized, there are times when tasks must be performed on live equipment. The main task here is that of troubleshooting. The point is that you cannot ignore arc hazards by having a policy that no one works around energized equipment. Obeying such a policy 100 percent of the time would be impractical, giving the troubleshooting dilemma. The only logical thing to do is to implement an arc flash safety program that meets the criteria specified in NFPA 7OE.
A proper and compliant program begins with an arc flash hazard analysis. This provides information that indicates the amount of potential energy that could be released during an arc flash. This is not something most companies want to conduct on their own due to the complex calculations involved. There are companies available like Predictive Service that has the engineering expertise to conduct a proper analysis. Once this is done, each piece of equipment will be labeled with information regarding the applicable hazard category. This will tell employees what level of personal protective equipment they need to be wearing while performing tasks while the electrical equipment is energized.
Injuries that occur as a result of an arc flash can be quite severe. The amount of noise is sufficient to cause permanent hearing damage. The heat can approach 35,000 degrees. The explosive impact can blow a person off the working surface. If this surface is a ladder, there can be significant injuries suffered as a result of a fall. Flying debris will cause cuts or become embedded into the skin.
Arc flash potential is not something to be taken lightly. A fully compliant program can save lives and avoid liability.