According to the National Institute for Occupational Safety and Health (NIOSH), an arc flash is the sudden release of electrical energy through the air when a high-voltage gap exists and there is a breakdown between conductors. In other words, arc flash happens when electricity is discharged in an uncontrolled fashion between improperly connected conductors.
As volatile as that sounds, it severely understates the potential for mayhem. Arc flash incidents kill workers every year. They also leave many who survive with permanent injuries.
With this in mind, let’s look at ways to reduce the likelihood of an arc flash.
Anticipate and Eliminate
Even workers with rudimentary knowledge of electrical theory should understand how an arc flash could result under certain circumstances. Compromised insulation is one of the leading causes of this phenomenon. If you open a panel and see worn insulation, you should assume you’re at risk.
Similarly, loose connections at pressure junctions can overheat and produce an arc flash. Always ensure all connections are solid in a system before closing a panel after performing any maintenance procedure.
There have been a number of technological advances in this area over the years. Companies like Schneider Electric offer switchgear and other components that resist arc flash.
These utilize engineering controls such as barriers, compartmentalization, and pressure relief mechanisms to redirect arc flash as well as the accompanying gasses and forces away from personnel.
Avoid Working on Live Systems
Energized equipment should be opened only when absolutely necessary. This will usually require a bit of pre-planning with the facility manager to avoid disrupting critical operations, but it’s better than putting lives at risk.
Follow the procedures outlined in NFPA 70E (2004) if a system must be worked on in an energized state.
Keep in mind that some devices contain capacitors capable of retaining a charge even after the system is shut down. It’s crucial to ensure these are discharged before any work proceeds. Appropriately rated voltage testers should be employed at each energy point to ensure no charge is present.
An energized work policy and accompanying procedures should be in place. This information should be in writing and workers should be trained to it on a regular basis. Conduct monthly safety meetings to remind crewmembers of the hazards and ensure they’ve been suitably informed.
Included among the procedures should be mandates specifying only qualified and well-trained individuals perform energized work. Jobs should be planned and thought through beforehand in an effort to identify potential hazards. Once recognized, suitable prevention methods to mitigate the dangers should be gone over by the team before work begins.
Use Personal Protective Equipment
This one might sound like a “Well, duh!” recommendation, but you’d be amazed to learn how many people ignore it just the same. All clothing should be flame resistant. Nylon, polyester, rayon or acetate garb should be removed before starting work. Petroleum-based fabrics are extremely flammable. Eye protection and gloves should always be worn as well.
You have a responsibility to ensure the safest possible work environment for your employees. As stated above, arc flash incidents kill workers every year. They also leave many who survive them with permanent injuries. These are but five of many ways to reduce the likelihood of arc flash to help you create a safer environment for your crew.
While arc flash is certainly a dangerous and unwanted occurrence, it doesn’t have to completely derail your business. Taking proper safety precautions and providing adequate training can help lower the incidence of arc flash.